My Daughter has just bought a G1 , Have to admit , I am very impressed with the UI , I had a little play with one a few weeks back , but I am must say I am much more impressed with it having had a proper play ..... But ...

Unfortunately we are having some trouble , Using her simcard , she can send SMS's , make outgoing calls , and browse t'internet , She cannot receive calls or SMS's - I performed a restore of the device , and after restoration , all the "test" messages we sent magically arrived all at once , as did the missed calls , but any new messages and calls simply didn't show up , and calls go to voicemail
Now the strange thing , is that we got exactly the same behaviour from my SIM (t-mobile) - Yet in any other phone , it works fine !
We are in a poor T-mobile reception area here (despite the Postcode checker showing good coverage for 3G & 2G ) so I think this is playing some part , but then calls to my wifes T-mobile N73 get through 8-10 times , so I am sure there is a deeper problem , lying with the G1 itself IMO

Shame as the UI is great !