Why Did Apple Force Stanza to Disable USB Syncing?

TechCrunch reported that last night an update to the Stanza app appeared in the iPhone App store–version 2.1–with a curious change: Lexcycle, the company behind Stanza, which was bought last year by Amazon, had removed a feature from the app at Apple’s request. The App Store page for the updated version of Stanza said that the update “Removed the ability to share books via USB as required by Apple.”