For example...
http://ax.itunes.apple.com/WebObjects/MZStoreServices.woa/ws/RSS/toppaidapplications/limit=25/xml
Right now, for me, that feed shows Camera+ as being the number 3 app paid app. However, on the iphone app store at this moment, Camera+ is number 4 and Fruit Ninja: Puss in Boots is number 3. In the feed Puss in Boots is like 8 or 9.
The timestamp on items in the feed appears old. I thought maybe it was some sort of caching issue on my end, maybe it is, but I've tried running this from a clear browser.
Also if I go to http://feeds.appstorefeeds.com/appstorefeeds-TopPaidiPhoneApps it shows Camera+ as being number 3. Still caching maybe? I don't know. Anyone have any insights?