My 4-year old iMac is on it’s last legs. The DVD drive no longer works and, although everything else is fine and functional, it’s just plain slow. I have the money, so what’s the problem?

It’s this: everyone was hoping for a new iMac to be announced at Macworld, but no dice. It’s been a long time since a new iMac appeared and it seems certain we’ll have something exciting by June at the latest. But I don’t really want to wait. I’m morally certain I could CAUSE something new and exciting to be announced and rapidly rolled out, by the simple act of buying one of the old ones. I doubt very much it would take more than a week. This would, of course, be intensely annoying to me. But everyone else would be very happy. They could buy whatever the happy shiny new thing turns out to be. (At the very least, they could buy the old thing that I just bought for significantly less than I paid.) So: should I let the knowledge that I will be bringing joy to millions of other mac users, in the form of a hot new iMac, tip the scales in favor of buying the old one right now? Should I buy altruistically, in effect? Bonus question: if I knew that by throwing a fat man off a bridge in front of an oncoming trolley I could make Apple release a new iMac, would it be ok to do it? So long as I didn’t get caught?

What do you think the odds are that Apple will 1) drop their prices or 2) roll out a new iMac in the next couple months?