The T-Mobile G1 phone has been fairly successful so far, although it hasn't yet approached usurping the iPhone from its lofty consumer throne. And so the rumours have already started about the possibility of an Android G2 phone.
The latest round of rumours started at Mobile Top Soft, which reported that the HTC Touch HD phone would arrive in the U.S. instead as the T-Mobile G2 phone running Google's Android OS. Cell Phone Signal then picked up the rumor, adding some preliminary specs for the G2 as well as the shockingly early release date of January 26. The rumor built up momentum from there until Boy Genius Report cited an anonymous source that Cell Phone Signal's report was fairly accurate with the exception of the date, which is now rumored to be between late February and April.
The specs for the G2 are reportedly almost the same as the G1 with some notable exceptions. The G2 will not have a physical keyboard of any kind, instead favoring a full touch keyboard more akin the iPhone. And though the G2 will be more centered on the touch screen, the track ball will remain on the phone for those who prefer it for navigation. The other notable possible addition is a VGA camera in addition to the existing 5-megapixel camera. The new camera should support better video calling, which would help differentiate the G2 from competitors like the iPhone.
Supposedly the G2 will also be available through other carriers than just T-Mobile. T-Mobile still owns the G1, G2, and G3 names, so it is unknown what other carriers will be calling it. (The Boy Genius Report's anonymous tipster also mentioned that sometime late next year we can expect a G3 phone to debut).