Android device support really depends on your carrier. Some carriers are MUCH better than others at releasing updates. If you're willing to go the unsupported

Android device support really depends on your carrier. Some carriers are MUCH better than others at releasing updates. If you're willing to go the unsupported route, most popular phones seem to have unofficial ROMs available. You can definitely get Froyo on your G1, and you might even be able to have Gingerbread. I think that the trick with Android is to get a phone that seems like it will be pretty popular. Don't get a cool but oddball device (I have a Droid Pro, which fits into that category, and a Droid2, which seems to be pretty well supported by the ROM community).