Well, I mean, back when I bought my Sawtooth, it was the second from the top of the line. 400mhz - and today the fastest pmacs are 2.7ghz - merely going by megahertz (not accounting for dual processors), that's a 6.75 fold increase. Guess that's what happens when you wait 5 years. So I hope for my next P-mac to be somewhere in the range of 3-4ghz, MP. However long it takes to get there, I'll wait.
But man, 5 years ago, 2.7ghz was mind boggling to my 400 mhzed mind. I can' imagine - will we be at 13ghz another 5 years from now? Will standard hard-drives be in the order of terabytes? What the HELL is big enough to fit on a 1 terabyte hard drive anyway.
Taking this further - mp3s were a huge revolution, because people realized that they could get sound almost as good as CDs (CDs do indeed still sound the best - despite Apple's claims about the awesomeness of AAC) in a little file, and would eventually able to keep tens of thousands of them on their computers. Will the next move be with movies? I'd put your average DVD somewhere between 5-10gb. With a 5 terabyte hard drive, will we be treating DVDs like the mp3s of the future?