Russell Beattie had nice post on Bloglines and Bloglines Mobile. I agree with all of his praise and suggestions and thought I would add a few more.
1) Update the ability to create blogs. The interface is weak, you can't post via email, it's tough to post via mobile.
1) Give me some way to rollup posts. Some times I want to only look at certain categories of posts and right now I have to scroll through everything
2) Make saving a post easier. Right now I can save some thing I want to look at later, but if I do that, I lose the stuff I haven't read yet.
3) Make it easier to come back to posts. If I follow a post to the sight, I lose the feeds I haven't read yet.
Once again, Bloglines and Bloglines Mobile are great, I just want them to be better!