Just to provide an alternate view to the m$ bashing...
No one is forcing anyone to upgrade. XP will be supported for quite some time, count on it. Look how long win2000 has been going.
Ignoring the bad correlation with vehicle gas mileage and computer resource usage, if you look at some of the things vista is doing it is actually
better than XP. First, when you fire up a game you get the same performance from the hardware whether the new-hotness aero interface is maxed out or you are running the old-and-busted plain interface. (look
here) XP is hardly that way as any new thing on the desktop "features" end impacts 3d performance a bit.
Looking at the stated goals at different times from m$, you see that under normal operation so much of the resources in contemporary machines sits unused in XP... vista actually uses it. (video card for the desktop, more ram for better caching etc.) This is actually the same argument I heard from an Apple rep speaking on the benefits of osX vs. winXP. He explained to me that it was one of the goals of osX; use those resources. Kindof a waste of hardware when it just sits there. As an engineer I see your point on efficiency but would rather use it if it is there than try not to and let it collect dust. To quote a wise professor from days gone by: "Memory is cheap... program it for what you will have, not what you had"
In all of these things, in order to actually use it (hardware) you need to make sure most have it. Thus the higher requirements for vista. On any machine from the last year you really should have 512 megs of ram or more, and IMO a gig is minimum. Vista is created for those machines. Not the athlonXP 1500+ with 256 megs of ram and a geforce3 video card. (not saying anything about your g4, just making a point) Even winXP struggles on that level of system. To make a piece of software that scales over systems from that many levels of performance is insanely difficult. You end up with something that kills the old ones or never really uses the new ones.
sure, you can turn off aero, caching and the lot... you can "dumb" vista down to a level that will run on a lesser system. (not as low as XP mind you) But at that point you might as well stay with XP. (maybe that was your point? dunno...)
Honestly, we need to move forward. If you don't want to upgrade the old computer... then don't and stay on XP. Simple decision IMO. Is that m$'s fault that you dont want to move from XP? nope.
I agree w/ you on the drm thing though. 8)