iOS 5 brings over 200 new features for the user. We’ve already covered what’s new in iOS 5 in extensive detail.
The public release of iOS 5 will be somewhere around Fall 2011 and iOS 5 supports iPhone 3GS, iPhone 4, first and second generation iPad, and the third and fourth generation iPod touch.
So if you are a developer enrolled in iPhone Developer Standard or Enterprise Program, you can download iOS 5 beta today for the SDK, by signing in to Apple Developer Connection.