Bill Flitter: Led by Bloglines, 70 percent of Pheedo managed feeds are read by only five aggregators. [cut] Pheedo is seeing Bloglines atop our feed reader statistics, followed by Firefox, Thunderbird, NewsGator and Sharpreader.
http://www.pheedo.info/archives/000265.html?rss-specifications
Randy: Pheedo's stats differ significantly from FeedBurner's or my own. I attribute this difference to the timing when these services came online and the customer base. Pheedo, a much older service, has Sharpreader, a much older reader, as #5. FeedBurner has BoingBoing and other top blogs using their service. Cross promotion of these services with My Yahoo! means that FeedBurner is gonna get a lot of hits from Yahoo! Further, FeedBurner has awesome podcasting support and this translates to more hits from iPodder, iTunes and the other podcatchers.