That is good news for the customers that Apple would be releasing iOS 5 in 2012, but the registered developers can get it from now.
You will get a lot of help from iOS 5 as it will support several devices like iPhone 3GS, iPhone 4, the iPad 2, the original iPad and the iPod touch 3G and 4G, along with that to the devices that Apple will release in the near future. In the future there would be updates for iOS 5 which will be OTA and in that only the changes will be downloaded not the whole firmware. So it would really be easy for the users to update firmware on devices that is running on iOS 5.
The big advantage is that iOS 5 has a total of 200 features for the easiness of users. Out of those two important iOS 5 features key features are; new Notification Center and the iMessage cross iOS device messaging client.
So from now on developers would be allowed to have iOS 5 and the other non-developers could get it in fall.