For me it's twice bitten... next time I'll be once shy. My iPhone was bricked with Error-25 on this update as well (2.0.1 bricked my phone as well). Luckily my wife's iMacG4 unbricks it well. Next time I won't be trying to update it with my MacBook Pro.
It's still updating, so no idea if it will make my reception better.
3G reception is still poor. Even after Updating to 2.0.2. A 2 years old Nokia phone has full reception on 3G, where in the same place, same network and same SiM card the iPhone has no receiption at all!
3G data service is bad to worse. I am located in major city with full 3G coverage. Recently I watch my partner download the same web page faster on 2G model then on my 3G. Contacts are still very slow, not sure what bugs were fixed but does not appear to have fixed either and still have echo on blue tooth in car speakerphone. I love my iPhone but am beginning to wonder if I should have kept the previous model? (Note: have done reboot, switched 3G off and on and called AT&T). Speakerphone on phone much improved, but product seems just not quite there yet...