The registration is devastatingly well thought through.
You customise the look of the site and import all your feeds before it asks you to choose a username so they can ‘remember’ you settings. By that time you’re already hooked as you have a sense of ownership.
You’ve also had change to play with another really snazzy feature.
Using a nice bit of Ajax the site loads in more and more content when you get to the bottom of a page. I’ve got my blog, Delicious, Flickr, Last.fm, Twitter, Tumblr, Stumbleupon and YouTube feeds imported and scrolling endlessly.
If you want to have a crack yourself here’s a JQuery implementation for endless scrolling.
It’s a really fresh piece of functionality but you should check it out for yourself: http://hellokinsella.soup.io/