According to Gizmodo and the fine people over at XDA Forums a leaked firmware upgrade for the Nexus One seems to address the 3G issues many users have been complaining about. The firmware is obviously not ready to be pushed out as it seems to be an old ROM with a revised radio.img . People have been able to hack it into CyanogenMod and report a much steadier 3G signal. This shows that the problems many users have experienced are software based and thankfully not hardware related as many have speculated. It also shows that someone out there is on the case and a solution is coming soon.
Editors note: I own a Nexus One and I have experienced zero 3G problems since day one.