The first beta of the iOS 5.1 has been seeded to the developers. The devices compatible with this version of iOS 5.1 are the same as before: The iPhone 3GS, iPhone 4, iPhone 4S, iPad 1 and iPad 2 and the 3rd and 4th generation iPod Touch.
The main thing to consider is that whether this beta will bring the battery bug fixes or not, as promised by Apple.
Before this, Apple released a minor update to the iOS 5, iOS 5.0.1 trying to fix the battery issues with the new iPhone 4S but completely failed to fix them. Just a week after the iOS 5.0.1 release, it was rumored that the iOS 5.0.2 will be released soon to finally fix them.
But it seems like Apple has decided to skip iOS 5.0.2 and directly jump on to a bigger and much better update, iOS 5.1. Lets see of what this new update brings with itself.
You can download this beta of iOS 5.1 if you have a developers account at Apple.[iOS Dev Center Link]