T-Mobile USA has confirmed in an online forum that it has started to push out an update to its G1 users. The update, version 1.1, looks like it fixes a number of bugs, but also adds a couple of new features. The most exciting is that Google (NSDQ: GOOG) is adding voice recognition to search, a feature that has already been on the iPhone for quite some time. T-Mobile is clear in saying that this update is not ‘Cupcake,’ which is an Android development branch that is a work in progress. The update started to go out to a small number of users yesterday, but will be sent to all G1 users over the next two weeks.

Other updates and features: Fixes Comcast (NSDQ: CMCSA) email, which fails to download more than one email; stabilizes text messages, which sometimes freezes; allows you to stay logged into IM when you turn Wi-Fi on or off. In addition to voice search, the update adds the ability to save pictures received as a MMS, and the ability to check for system upgrades.