(Update with official info) T-Mobile will officially put Google's Android 1.5 on G1 smartphones early next week, the company said today. In spite of having already pushed the update early to some users, T-Mobile USA hopes to have the update begin in earnest before the end of next week. The rollout will take place in phases to manage the load and will let every phone get the update by the end of May.

Android 1.5 includes the updates from the previously codenamed "Cupcake" update and adds a software keyboard, stereo audio for Bluetooth, video capture as well as offline playback, and photo uploading to Picasa and YouTube. Numerous improvements to existing features also come along and involve a faster web browser, a more responsive camera app and a quicker lock-on time for GPS mapping.