Android 2.3 SDK is out. There's no OTA update for Nexus One yet. Nexus S release was announced for December 16th, so there will be something out by then for N1 presumably.
Not sure how much luck we'll have rolling our own Gingerbread build quite yet. We still have no kernel source or any other source code from Viewsonic for that matter. Basically, I'm pretty sure I'll have Gingerbread on my Nexus One well before my G Tablet.
BTW, there is some explicit stuff surrounding large screen support in the Gingerbread SDK. Sort of a recognition that there are now tablet devices out there even though they won't be blessed until the 3.0 release.