How to manually flash todays Jelly Bean update to your GSM Galaxy Nexus | Android Central

So you want Jelly Bean, but don't want to wait for your turn at the OTA and don't want to flash a custom version of it. We completely understand -- Not everyone is into that. The good news is that a little bit of hackery (just a little, we promise) and an unlocked bootloader can get you some tasty Jelly Bean with no wait.

http://pulse.me/s/b8fee