iOS 5 to be released on October 12
The new features include Notification and Game Centers, iMessage, Newsstand, Twitter integration as well as other features. iOS 5 will be available for the iPhone 4, iPhone 3GS, iPad 2, iPad, as well as the third and fourth generation of iPod touch.
Apple has also announced the new iPhone 4S with many new features and boosted specs under the hood. The iPhone 4S will be released on October 14.