Two things that annoy me about bloglines so far...

If you don’t specifically “log out” then you are logged in the next time you go back.  Great for my home machine, not so good for any of the other machines I may deal with.  There should be a checkbox that you can select to “remember my login on this machine”.

Everything is already marked read when you select a feed, or worse yet, select a folder and all posts for all the feeds in the folder are marked read.  Grrrr…. James Avery warned me about this.  This is one thing that I liked about Newsgator online, there you would click each post to be read or not read.  That way if I was 10 posts behind I didn’t have to worry about having to “reset” the ones I couldn’t get to still be unread for my next visit to the site.