TechCrunch had a guest author, Frank Gruber, write about the The State of Online Feed Readers:
There are a number of different types of readers: web-based, desktop, Outlook based, etc… This post is focused solely on web-based feed readers. I’ve included the big guys plus some up and coming readers with outstanding features and/or performance like News Alloy, Gritwire, Attensa and FeedLounge.
Being TechCrunch, the review was primarily focused on features and technology of these aggregators, rather than ease-of-use over a longer time period. In the hundreds of comments are pointers to a few other web-based feed readers that people enjoy. And there are even corrections to the information presented from loyal users of the reviewed technologies.