I upgraded my iPhone 3GS to iOS 5, and I have to say, it's a pretty amazing upgrade. Notifications now no longer intrude like an irritating cousin, and the new Notification Center is really cool! The dictionary has also been greatly improved, which makes typing messages A LOT easier. And I really love iMessage, which allows FREE messaging between iOS 5 devices INCLUDING iPod touches and iPads! The only downside? iOS 5 finally broke Stanza, which I think is the best e-book reader for the iOS platform! After upgrading to iOS 5, I tried to continue reading my book on Stanza, only to get this error message : From what I read, Amazon bought Lexcycle, the developer of Stanza, and stopped development of Stanza since 21 February 2011 (for the iOS version). Stanza is apparently using depreciated code that has been removed in iOS 5, causing it to fail. Arghhhhhhhhhhhh!!! Now what do I do??? Well, it looks like Amazon has absolutely no intention on further developing Stanza, so I guess I have no choice but to explore other alternative e-book readers.