The update seems to be targeted at unlocked and unbranded Nexus One devices. It doesn’t appear to be clear as to what the Gingerbread 2.3.6 update is bringing to the table, but it doesn’t seem to have any major changes and is most probably a patch to fix security/bugs that may be evident in the previous update. The good news is that while the 2.3.6 update seemed to have messed up WiFi tethering for some Nexus S users, the Nexus One has been reported to have no issues with it.