The practicality of the platforms also 'trump' technical abilities.
I'm sure even my Windows 2000 PC is pretty stable. It should be: I've essentially built a stable system, then 'frozen' the configuration. It's built for one purpose -- playing games -- and it does that superbly. I dare say, even if I were using it for day-to-day work, it'd also perform pretty stable.
But here's where uptimes may mean absolutely nothing whatsoever for home users. I simply cannot leave my PC turned on. Even in sleep mode, the PSU fans still run, making a very bedroom-unfriendly racket. Sure, I can use hibernation, but I've got two problems with that: Going into and out of hibernate isn't instantaneous. My boot times are already under 1 min (lots of RAM!) ... and the only thing better than that which has any meaning is 'instantaneous'. Also, I've had the machine fail to wake from hibernation once or twice -- I don't want that sort of uncertainty. It's got to work right 100% of the time.
My Mac Mini always has great uptimes. Sleep is instantaneous and silent. Waking is similarly instant, and has so far (10 months) not failed or even given the hint of failing even the once.
So perhaps uptimes shouldn't be used as a marker of stability. Instead, they can give a clue as to how the 'whole package' affects usage.
Since my Mac's unobtrusive, but always available when needed, it means it can perform roles which my PC simply couldn't -- through no real fault of Windows... it just wasn't designed with what I want in mind.
For example, when my phone alarm wakes me up in the morning, the Mac will wake too. I can take a quick glance at the Mail icon to check for the 'new mail' count on my way to the shower.
I can leave the machine alone, knowing it'll happily go back to sleep if I don't need it. I can take notes, add contacts and appointments to my phone during the day. As soon as I've got the key in the front door, the phone's proximity has woken the Mac up and they're already sync'ing information without me touching a thing (or even feeling like I have to check to see if it's worked. It always does.) My mac's email addresses, address book, calendars will just simply be updated. There's no roaring of fans, beeping of speakers or anything that makes me feel like I'll have to put my geek hat back on after a day in the office to make my home machine do what I want.
They're the sort of experiences that Windows and the PC platform can't give me yet. I know some of that might sound pretty fussy... but it's those little touches that make me feel that both the Mac's software and hardware have been designed with the intention of doing useful things for me... not of sitting about waiting for me to make it do stuff amidst a howl of fan noise
[edit] ... it's also the small touches like those I've mentioned that can bring a real shift in how a computer's used. I've used computers for 20 odd years. I've seen untold numbers of address book and calendaring apps. Occasionally I'd put all my data in, and for a week or so, I'd actually use it. But I'd always end up back with good ol' paper and pen. The information would be locked up on the computer. Or, it'd be on a portable device that I'd have to remember to synchronise somehow. Even if that were automatic, I'd have to ensure the computer was always available and working... which I'm afraid just isn't practical with most of the machines out there.
Incidentally, this is one of the reasons I feel Intel were always so keen to get Apple on-side (apparently for over 5 years pretty much constantly, and occasionally over the Mac's life). Intel make processors... but they're just a component in the PC platform which really hasn't done anything particularly 'cool' for the user in a long long time. Intel will now be involved in Apple products which can really show off Intel's processing, wireless and multimedia hardware without the encumberances of the PC platform. If I were an Intel engineer, I'd be pretty excited at the prospect of seeing the kinds of systems Apple would be building with my stuff.
