True, if you don't have the money, wait, however, even if the first G5 PowerBooks come out tomorrow I'd rather have a G4. The G4s have all the bugs worked out now, and Apple is notorious for having very buggy first revision products.
And yes, Phoenix, no one disputes the fact that 64 bit is the future, however, there are no major advantages at this current time to buy 64 bit. By the time software stops coming in 32 bit your computer will be so out of date anyway that you'll probably've upgraded several times already.
The advantages of 64 bit right now over 32 bit are slim and nowhere near enough to warrant waiting for a G5 PowerBook if you're in the market for one now.