Ratings for blog posts

I use Bloglines for reading blogs because I can access it on any computer and my list of blogs is always right there. However, there are a few things I would like to change about it. For example, I would like to be able to copy and paste my "blogroll" easily so I could transfer it to my blogs and show other folks what I'm reading.

Another thing I'm interested in is ratings for blog posts. It would be really cool if there were a network of ratings for each post that a reader could use to sort them and figure out what's worth reading. If one were able to use the ratings of people whose tastes were similar to one's own, it would be a form of social software, too. That is, something like, "This person often likes posts that I like; therefore, I will probably like this other post that this person likes."