G1 owners in Germany are set to receive a software update in May, according to the T-Mobile site. The update is based on Android 1.5 and promises an on-screen keyboard, video recording and playback, new home screen widgets, stereo Bluetooth support, and more. As with other updates, it will be pushed out automatically over the air.
While there is no similar page for U.S. T-Mobile customers, it is likely that they will see the same update around the same time.
Note: The ‘More information’ link is in German. [Google translation]