Matthew Hurst has some data debunking the concept that the A-list of bloggers uncover the newest things first:

I do believe, however, that there is steadily increasing delay in ideas getting picked up and amplified by the A-list. Of course, this is the type of claim that needs far more than the single point of anecdotal evidence that I'm going to point to, but the hypothesis suggests that, as the blogosphere matures, how it operates, and the role and influence of the A-listers is going to start mirroring much of main stream media.

Are A-listers getting lazy?