The T-Mobile MyTouch 3G is due to launch in the US in August, however the handset has been available elsewhere in the world. The Google Ion shares the same hardware as the T-Mobile MyTouch 3G and so Cnet has compared the two.
Storage space on the G1 is a top criticism with the OS taking up most of the space leaving just 71MB. The Google Ion now has 512MB of storage so doubles that of the G1 and although shared memory is expected to change on the MyTouch 3G there should be some improvement.
Battery life is another concern with the G1, having the turn off WiFi and GPS and so on to conserve the battery, but due to the 1300mAH battery in the Google Ion this is no longer an issue.
As for form factor, the MyTouch 3G loses the physical keyboard and will have a larger trackball and redesigned navigation keys.
So should you upgrade? It?s probably a personal choice but for me the G1?s physical keyboard is why I purchased it in the first place as I prefer it for texting, so I?d probably give the MyTouch 3G a miss.