So I got my rev. B PB 12" on Tuesday. So far I really like it. I'm really falling for OS X. It's my first Mac.
The machine is very well constructed. There are a few minor quirks, although some might bitch up a storm about them, Im to happy with everything else to worry about this petty stuff.
Their is a very slight separation in the case just above the latch, to the right. I've read about several other people who have the same thing, doesn't really bother me.
The F1 key seems to be a bit sticky, but still functions ok. That's about it.
Everything else seems to be flawless. No dead pixels, screen is beautiful. Airport reception is good, although I haven't taken it that far from the Access Point yet.
I get about 3 hours on my battery if I lower the screen brightness a bit. I'll have to experiment with more.
Overall, I'm very pleased with my purchase. I've been following Apple closely for a couple years and I finally jumped in. It seems like things are only going to better and more exciting for Apple. I love their hardware, the designs and their OS is fantastic.