John Battelle's Searchblog, very popular search related news and opinion blog, asked the question in his entry named This Is Odd; why was Feedster and Blinx taken out of Google's results?
Soon after, GoogleGuy shows up with a comment, see the 6th comment down. Not bad. :) The bottom line is "Given that the issues appears to be on Feedster's side in this case, if they'll start serving Google a normal page again instead of a 404, I would expect their root page to be back right as rain in a few days."