What I have: Mac Mini G4 1.42 - I bought this machine shortly after the Mini was releaed to serve as a test bed to try out OS X. Office (I neeed it for file compatibility for freelance writing projects), E-mail and web access were the initial uses I had in mind, and it was kind of nice to have a near silent machine for casual use. With advancing to a PowerMac in mind, I picked up a copy of Adobe CS2 (some frelance writing projects involve Illistrator work and some light Photoshop use). I figured that if the Mini could not hack it, then I would progress to a mid-range PowerMac as planned. With a 1GB memory upgrade the Mini proved reasonably usable, and I was now at the point where 95% of the software I was using was running on it. Have to hand MicroSoft a lot of credit - by making Windows so much more like OS X they made the transition much less painless (Vista users should find it a virtually seamless transition by the looks of things).
What I'm going to get - I plan to follow through on the idea of upgrading to a more powerful Apple machine. I was all set to pull the trigger on a PowerMac when some fool went an announced the swich to Intel. Given that the Mini had performed so well, I figured I could tough it out until the PowerMac was replaced. So now that has happened, the time has come.
When - Real soon. I'm giving it two weeks or so to see if any problems surface. I'm not anticipating any, for the transition desktop machines (Mini and iMac) have had few problems and the processor, memory and chipset have been in the hands of not only Apple, but many other manufacturers - which means that unlike Power-based systems alot of the tech had been through the wringer. This is an advantage of the switch to Intel that few appear to have appreciated. If there are any problems I am sure we are going to hear about them "real soon".
Why - As capable as the Mini has proven itself, I've been working on a project that has pushed the little thing to its limits. Right now the key is memory. I have a perfectly good 20 inch CRT that has a few more years in it - so an iMac is not a real option. None of the other Apple products have the capacity for significantly more memory. The Intel Mini can take 2GB it is true, but any advantage of faster processor or larger memory is currently lost to the necessity of using emulation to run Illustrator (in this case). So I need somethig that can take at least 4GB of memory (the mythical Mini Mac Pro probably would max out around 4 GB - so even if such a beast were to be released, it would not be that attractive, being as it were a short term solution). Right now that is the Power Mac. Second, I'm dusting off my Lightwave licence (some 3d image work ahead), and that is an application that just loves all the memory you can feed it - and also one of the few applications I have that gets a real benifit from a multi-core architecture). The Mac Pro has come along at just about the right time for me. I'm inclined to go with the stock graphics card (the applications I use don't get much benifit from a high performance card) and use the money on memory (more memory - the eternal cry rings out). Real question is which processors to go for...
Then I can retire this old Dell I have under my desk which I have not turned on for a month, and use Parallels to run a clutch of programs I may still need once or twice a month.