Apture - freaking amazing new way to add metacontent to your site

You've seen those popup windows that come up when you mouse over some links on various sites - annoying and usually in the way. That was my first thought when I saw Apture. Boy was I wrong. They have taken the idea of adding metadata to your site to a whole new level of polish and ease of use. Plus, the UI is actually really pleasant to use and not "in the way" . Just add a bit of js to your blog, then run a bookmarklet when you are on the site and you can just highlight text and add flickr photos, wikipedia entries, and other cool things like google maps. If then open the api for third parties to add "widgets" this could be a really BIG DEAL. I wonder who's going to buy them up when the big co's discover this site.