It basically enables the phone to ignore its kernel and allows the phone to run from a custom kernel that is built into the ROM. This should enable developers to have bug free ROMs in the future.. and also a jelly bean ROM that works.
BTW I've flashed every ROM available Lol
(I'm hooked). Anyway if you value battery life then go with a blur ROM like read head or liquid blur. . The best aosp option at the moment is speed lite (not the aokp) it has less battery drain than other options.
I would rather run aosp but I can't charge my phone all day, so I run liquid blur.
Obsidian's for ICS Leaks /Root/Roms/FXZ/RSD/Threads/Guides/SafeStrap/Bootstrap/***All Download Links in OP Updated Daily*** - Droid Bionic - RootzWiki <-- obsidians ROM thread.. shows everything you need in one place
Gonna try Speed Lite V1.1. I love Liquid Blur, but during phone calls the display turns off and won't turn back on. For some reason my phone does this with many, but not all ROMs and it doesn't happen stock.