iOS5
If you can't wait for iOS5, once the GM is out, you can download it from some external site and load it on to your iPhone. The GM never has restrictions to only developers like the betas do. That's how I was able to claim my Game Center name before everybody else. I got iOS4 before anybody else by installing the GM. The GM will be out on Tuesday and pre-orders for the iPhone 5 will start after Tuesday. Expect iOS5 to come out just a few days before the iPhone5 and 4s.
If you can't wait for iOS5, once the GM is out, you can download it from some external site and load it on to your iPhone. The GM never has restrictions to only developers like the betas do. That's how I was able to claim my Game Center name before everybody else. I got iOS4 before anybody else by installing the GM. The GM will be out on Tuesday and pre-orders for the iPhone 5 will start after Tuesday. Expect iOS5 to come out just a few days before the iPhone5 and 4s.