The first beta for iPhone OS 3.1 and a matching SDK were seeded to developers on Tuesday night, with around a dozen new extensions for the OpenGL ES graphics library that developers can use to improve graphics exclusively on the iPhone 3GS. Among the new features the ability to select video recording quality and a couple of new app interface classes. Xcode 3.1.3 has also been released.

The new iPhone OS release is coming unusually soon after 3.0. In the past Apple has preferred to address bugs in minor patches rather than more significant revisions that often contain noteworthy new features. So far, nothing contained in iPhone OS 3.1 is believed to have added significant features. Perhaps it’s a move to encourage the adoption among iPod Touch users, which are moving to the new OS more slowly then initially anticipated?