After years of using Bloglines, I switched to Google Reader for my feed reading frenzy, and I'll never look back. What a fantastic Web app.
I have to admit though, that one of the things that made it so easy was that Bloglines allowed you to export your feeds, even with the categorization, into an OPML file. That made it a snap to instantly start using Google Reader. It even puts little Flash audio players in the stories if you subscribe to a podcast. Very slick.