I'm pretty sure Google stopped the 2.3.3 OTA, i've been searchin all over the internets, and almost no one have gotten the 2.3.3 update over OTA, i belive it was out in a matter of hours (might be a day or two). And then the rest who have it manually upgraded it.
I've seen post of people getting the phone with 2.3.3 installed on purchase, but i think this is also very rare.
What really made me belive for sure they stopped the 2.3.3 are that alot of people who had 2.3.3 (and some 2.3.2) and were complaining on some issue hardware or software and they took their phone back and gotten a new/repaired and got it back with 2.3.1 and even the 2.3.2 OTA wasnt available for them.
So whatever bugs that are out in the OS, it seem like 2.3.1 is the stable one for Nexus S.
I will wait and hope Google release something after Google I/O in May 10.
Me want some delicious icecream.
btw, im stuck with 2.3.2, no issues. Dont want manually upgrade, bcause i dont wanna loose ma colours 'n contrastz
sources
did anyone get the 2.3.3 ota yet from Google - Google Mobile Help
Did you receive android on 2.3.3 on Nexus S ? Today is March 16,2011 and I still have not received OTA update - Google Mobile Help
and there is alot more