I upgraded my 2g iphone and had two problems: youtube doesn't work and when wifi was off, the locate me function in maps didn't work and I got a message saying that it couldn't determine my location. I looked all over the place for a solution but nobody seems to have one. Then I tried resetting the network settings under General - reset - reset network settings. It rebooted and now the location manager works perfectly again. Unfortunately, youtube still a no go. Just FYI in case anybody has the same issue -- it may be as simple as resetting the network.