This is almost shocking to me! Before this tweak 1 hour usage and 2hr+ standby is no way around 80%+ so either Im smoking something or this tweak did some magic! I will report back later with more stats.
If they are collecting UDID's, then they already have it. Nothing you can do now.
I have noticed better battery performance, but I want to give it a few days to draw conclusions. My 4S has had dreadful battery life since 5.01. Before 5.0.1 it was similar to my iPhone 4.