There is nothing saying the 930 will be 32nm. It is more likely that it will simply be a C2 stepping, maybe C3, of the 45nm chip we've all known and loved.
You're fine with your 920. I just got mine 2 weeks ago, and it overclocks to 4.2Ghz with only 1.275V core voltage. I don't believe the 930 will overclock any better.
Better steppings do usually increase overclocking potential, however, the 920 at 4.2ghz is beast. If your deal is gaming, the CPU is not the culprit to low fps