If you don't need it right away, then why do you need such a powerful machine?
You are going all out, for fun?
What do you plan to use it for?
i'm in the same boat. my dual 2.5 PPC G5 (6.5gb RAM, 6800 Ultra, 9800 pro, 500gb samsung, 1tb WDCB) bit it at the end of november, and i need a powerful machine when the new ones arrive. ... but as my great grandmother used to say about shoes, "i don't have the money to buy cheap things," meaning that i will need to squeeze every day i can out of the new machine.
since nobody is paying me to use
my own computer at present (for the next few months i can tutor FCP in my school's computer labs instead of in my apartment and i have access to a top-tier post production facility) all i really "need" to get by right now is this old PC laptop, my external HD's, and a SATA/IDE to USB converter.
however, when the new model comes out, i will be making full use of the max performance specs that i can afford for my own work.
the reason i haven't bought the current model yet is that i plan to have the computer for 5 years... 20-50% gains in performance for video work over the current generation over a five year period is absolutely worth the wait if you're on a budget...because these upcoming machines are so powerful, i'll be able to grow into it (as my budget grows i can upgrade)... hopefully, clients will buy my next mac pro. for now, i've got my student adc membership and $5k set aside, even if that's a HUGE amount of money to me at present.
considering that there's plenty of economic gloom on the horizon, having the best machine i can have will really go a long way if i'm trying to build my reel or freelance. i spent a lot of money on my last computer and i absolutely returned my investment by making professional quality student work.... with which i've made $0 but have gotten excellent professional opportunities.
since i'm somebody who can wait, (no demanding deadlines or a yearly tech budget yet) i'm clearly not the pro client apple is looking for, but i feel that i and people like me are making a very wise decision to wait.