Apple announced on Wednesday a cornucopia of new hardware and software: sleek iPods, a brand new Internet-enabled video streaming device and new versions of its iOS software and iTunes 10. However, the most impressive to me by far was Ping, the music-only social network that Apple is opening up its 160 million existing iTunes users.

No, I’m not blown away by the 160 million number. What I’m impressed by is the thinking behind Ping.

Ping may function like a cross between Facebook and Twitter for iTunes by allowing you to follow celebrities, create social cliques and get artist updates via an activity stream. I think it could have tremendous impact on social sharing and commerce.

From a content perspective, there are three different types of media we love to talk about: movies we see, music we listen to and books we are reading. These are accepted social norms. In fact, many relationships are made on the basis of collective love of a movie and many friendships have started with mixed tapes.

It makes perfect sense for a music service to be social. I’m not alone: The popularity YouTube, the fast-growing MOG and the sadly defunct iLike and Imeem show that people gravitate towards music as a common, collective experience. A recommendation from friends on Last.fm often resulted in me buying many-a-few music tracks. My friends who listened to Thievery Corporation turned me on to The Broadway Project and Chris Joss, which I ended up buying on the iTunes store or via Amazon’s MP3 store.

This click-and-go-somewhere-to-download model of affiliate links can never match a unified experience. Amazon, for example, encourages bloggers and others to link to things they like and then get a piece of the action. This separates social from commerce and treats them as two discrete activities. On the post-Facebook Internet, I don’t think anyone can afford to keep these two actions distinct.

Ping, from what little I saw during Steve Jobs’ demo, allows a similar level of social interaction. It can tell me who my friends think are cool and the top 10 favorites of people in my social graph. Some of my friends are famous deejays. Others just have eclectic musical tastes. They can collectively sift through over 10 million songs and help with the discovery of music. This social-powered discovery is part of the biggest theme of our times: serendipity. About two years ago, when I wrote about serendipity, I said:

The problem is that there’s too much data coming online too quickly, and the traditional method of search that involves first finding and then consuming the information is not going to work for much longer. There just won’t be enough time for us to do that and still have a life. It’s a problem, and therefore solving it is an opportunity — a very big opportunity.

My belief has only been affirmed by growth in the amount of data available. With 12 million songs and 250,000 apps, the best way for Apple to enhance the iTunes store – aka its shopping experience — is through the use of social. Back in 2007, I argued that social networking was merely a feature that had to be embedded into applications to enhance their value. Apple has done a great job of that, but it’s also gone one step further, not only by adding a social networking layer to iTunes, but by meshing it with its commerce engine, the iTunes Store. And it’s made this experience available on both the desktop and its devices.

Apple received much of this social capability with the acquisition of Lala, an online music service, which as a standalone company used sharing of social objects to drive folks towards paid music downloads. Now Apple is only closing the loop by further sharing what users bought. I wouldn’t be least bit surprised if sales of music on the iTunes store rocket upwards, thanks to social discovery.

Amazon, which recently started experimenting with Facebook Connect, has similar ideas, but its implementation leaves a lot to be desired. On Amazon, I’m reduced to reading reviews from absolute strangers for music. I have a handful of friends who have impeccable taste in non-fiction business books, are all members of Amazon, and they already use email to share new book suggestions with me.

What if they too could share their likes and dislikes via a social layer inside Amazon.com? Or what if I could follow my favorite authors and get updates on their books? Much like Apple, Amazon owns book-based social service, Shelfari, and should find ways to embed the social layer inside of all Amazon products and connect its tens of millions of users.

Like Apple, Amazon too has a lot more data about its customers and their behaviors and could create a compelling discovery experience. I believe with tens of thousands of products in its store, the retail giant needs to figure out ways to surface content and other offerings smartly.

Related content from GigaOM Pro (sub req’d): Why Google Should Fear the Social Web

Are you addicted to Twitter? Do you have an iPad? Even if the answer to both is “no” right now, after you see Twitter for iPad, those answers are going to change — quickly.

Yes, the wait is over. Launching tonight in the App Store is Twitter for iPad — the first official native iPad app from the company. We all knew it was coming (Twitter even said so a few months ago), but it has been a long wait. It was definitely worth it.

Like most people, I wander into hyperbole from time to time. But it has now been a few days since I first played with Twitter for iPad, and I still think it is hands-down the best iPad app out there. It’s that good. With all due respect to Reeder, Instapaper, Flipboard, and Pulse, this is now going to be my go-to app for just about everything related to reading news. It’s simply such a great experience for reading tweets — and more importantly, reading the links your friends share.

What Twitter has done is create an amazing user experience for reading information. This is thanks to an intuitive user interface that layers on top of itself. So, for example, if I click on a link in my tweet stream, I’ll have a new layer that rolls over to show that webpage in a customized browser window. If you’ve used Flipboard, it’s somewhat similar, but better because it’s much easier to go back to where ever you previously were before you clicked the link. You simply swipe something to the side to move it temporarily or swipe it again to get it off the screen (in portrait mode anyway, where there’s less space).

Something else that’s awesome: when you highlight a tweet by clicking on it, it’s now pinned to the top or bottom of the screen as you scroll through your stream. This is great if it’s something you want to reference. A lot of thought has been put into these type of saving state actions within this app. It’s simple to save a draft and go back to it, for example (much easier than with Twitter for iPhone). Or to reference one of these pinned tweets in your own tweet.

There are also some great new gestures that Twitter came up with for this app. For example, if you pinch-outward on a tweet, it will unfold to show you more information about the Twitter user. Better may be the way you can swipe down with two fingers on any tweet to see a full conversation in context. It’s the little things like this that make the app great — Apple-like, even.

Overall, the app looks and feels quite a bit different from Twitter for iPhone (which Twitter built from Tweetie — developer Loren Brichter’s client that they acquired earlier this year). But Twitter’s Leland Rechis assures me it’s using all the same stuff on the backend. In fact, Twitter is now a universal app — meaning it’s one app that will work on both the iPhone and iPad, it will just look different depending on which device you’re using it on.

Rechis also says Twitter started experimenting with some newer things on the iPad version that haven’t yet been brought to the iPhone version, but undoubtedly will. A great example here is that when you click through to a user’s profile page, you’ll see at the bottom a list of users similar to that user that you may like to follow.

Rechis also notes the importance of the logged-out view — something Twitter worked on before the iPhone version launch. Twitter wants to make the service as useful as possible to people even if they don’t have an account. The idea, of course, is that they’ll hopefully sign up for one — and this app may give them the most reason to yet. When logged out, you’ll be able to see tweet streams based on hot topics.

“Tweets in general are not just what I’m doing, they have an incredible amount of metadata,” Rechis says speaking to why they created this layering idea for the app. Almost 25 percent of all tweets now have a link in them, he says. This app is perfect for those tweets, and content consumption and exploration in general.

Rechis notes that one of his favorite things about tablets is how they eliminate window management. At the same time, you need some way to manage all this information. He notes that Brichter’s original concept was stacks of sheets of paper that you quickly shuffle through. Other members of Twitter including Rechis refined that idea and the end result is Twitter for iPad.

That’s roughly 750 words about the app — but you really just need to see it, and use it. It will definitely be my go-to way to browse Twitter from now on. It’s that good.

Look for it in the App Store shortly. It will be a free download.

Update: I should note that for some of these more advanced gestures, there is a slight learning curve. That said, you can do everything without using those gestures, so it’s not a big deal — it’s just icing on the cake. And yes, Twitter is trying to come up with the best way to teach users about these new gestures.