OK, the other (memory) thread got closed, and it brought up an interesting question: someone said that standby wasn't sufficiently "off" for air travel. Now, granted, there's some power going to memory in standby but that's as off as say, a PDA-phone in flight mode, which most people seem to recognize as OK.

So... which do you use? Why?

I use standby pretty universally - it goes to sleep quicker, starts up quicker - and don't even have hibernate enabled. My system has made it just fine (with some at-airport use prior to my flight) from Hong Kong to SFO on standby, with enough power left to get looked through by customs. Most flights aren't 12+ hour transpac.