I was waiting to get my G1 last week. Called up T-Mobile and they informed me that I can have the G1 but I will have to create a second contract with them until my current contract runs out. Slightly gutting that I now have to wait until May 2009 for my G1 (unless I fork out £300 for the handset).
It could be good this though, it could be that a better Android phone is released by then. Motorola are currently lining one up for release in Q2 2009. They are claiming it will be much better than the HTC model. On playing with the G1 I did find it rather large in the hand and of a large width. The way the screen opens too seemed like it could be easily breakable. I also found the qwerty keyboard hard to use. Will see how the reviews for the G1 pan out.