The phone has been reported to restart with no apparent reason in various circumstances, but most often during longer calls. Some users reported that their phone would restart even during a shorter conversation and this definitely qualifies as a dead serious issue. It is not yet clear whether it is a software malfunction or if the problem is in the hardware. With Best Buy's two-week return policy running out for many soon, hopefully some information will appear soon that will shed some light on the issue.
While we hope that this is not a
hardware problem, a Gingerbread-related problem would also be a misfortune for Google as they chose the Nexus S as the showcase handset for their latest version of Android. Have you experienced the same frustrating issue on the Nexus S?
source: Google Mobile Forum via IntoMobile