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. Keep in mind there is no way to get an accurate barometer of what users are seeing the issue more, GSM or CDMA, because this site is dedicated to CDMA version but we are going to put the question to you, the readers, anyhow.
Are you seeing random reboots? If yes, CDMA/GSM?
Is it region dependent, area dependent or it does not matter? Does it happen while streaming music, playing games, or simply when the device is left to do nothing?
Source: Google Support