The Samsung Galaxy Nexus is going through some growing pains and this one is of the undesired kind. Wide spread reports of random reboots are plaguing the handset and users are jamming up Google's Support Forum looking for answers.
It does not appear to be isolated to the GSM version only. CDMA users are reporting the problem as well. To what extent we are unsure but we'd like to find out.
Are you seeing random reboots? If yes, CDMA/GSM?
Is it region dependent, area dependent or neither? Does it happen while streaming music, playing games, or simply when the device is left to do nothing?
Source: Google Support