Surely you've heard of Pinterest already. Even if you haven't clicked through the headlines you know that Pinterest is the current darling of the Social Web; everyone is talking about how cool it is and how it's a breath of fresh air in the overwrought social media universe.
Pinterest is all of that and much, much more.
First, the basics: Pinterest is a social media site which allows users to create virtual pin-boards (think, cork board) where they can stick cool stuff they find on the Internet. The things they pin can be photos, videos, links to articles; whatever is interesting to them. It is very much like a typical bookmarking site only much more visual. The things which are pinned can be "Liked", Tweeted and Commented on, meaning there is a lot of interaction and sharing. In fact, sharing is the backbone of the site.
Second: Pinterest is still an "invitation only" site, which means you need to be invited if you want to participate. They are fairly loose about handing out invitations, however, so if you really want one you can get one. Just ask. Given its rising popularity it seems likely Pinterest will throw its doors wide open soon enough, making it possible for anyone to come along, set-up shop, and start pinning their favorite stuff. If you're a small business, let's say a bakery, you could open an account and start pinning up photos of your daily baked goods, best looking cakes, cookies or whatever. This scenario transfers to whatever it is you do and whatever you want to share.
Third: Pinterest interest is only going to last so long. That's right, I said it. Pinterest is pretty cool right now, but it's essentially very much the same as micro-blogging sites like Tumblr which allow people to post short snippets of all sorts of things and share them with others. The fact that you can share across multiple platforms does give Pinterest an edge, but only a slight one.
It certainly wouldn't hurt for you to start using Pinterest now so you can become accustomed to its inner workings later, but don't start thinking you're already behind the eight-ball. There is plenty of time for you to figure their service out before it goes fully public. And in my opinion, it's unique qualities are only going to last so long in the shark infested waters of social media.