iPhone 4.0

Details of the new OS for the iPhone has been released at a recent Apple event.

The 4.0 OS will ship in around June and have many new features such as:
 
Multitasking
Fast app switching
Local notifications
App folders
A new Mail app
iBooks
Custom backgrounds
Game Center
iAd advertising
5x digital zoom
Bluetooth keyboards

More info and pics at: http://gizmodo.com/5512635/iphone-os-40-all-the-new-features