I've just bought a MacBook Pro. My old laptop finally died, and when looking round comparing specs I discovered the "macs cost more" thing to be pretty much untrue. Sure, you can get a half decent laptop from a "PC" vendor for less, but look what it's actually got inside it... once you start comparing like-for-like specification-wise, there really isn't that much difference.
I'm a Linux-user by preference, and Microsoft consultant by trade (the quality of their software is so poor it'll keep me in flying hours for years to come), and the MBP now runs triple-boot OSX/SuSE/Vista. The aesthetics of the machine, attention to detail and the thought put into its design are fantastic; simple things such as the use of quality, branded hardware with plentiful driver support instead of obscure rubbish from some half-baked upstart who only ever bothered to write drivers for Windows. I randomly discovered the other day that when you pop the battery out, it doesn't just suddenly die - that's right, it will retain enough juice for you to change the battery without rebooting!
Apple's strategy of moving to Intel chips and binning 30 year old legacy stuff like BIOS is a good one and holds substantial benefit for those who want to lever that technology. Think if it as ripping out all your old, traditional, knackered avionics and putting a G1000 in.
Vista, that's an interesting one. As computer use has grown over the years, so has the average capability of computer users to administer their systems. Yet conversely with Vista, Microsoft do their best to isolate you from doing what you want, instead forcing you to do what they think you want. It might keep joe public (who quantifies resource-hungry eye candy as progress) at home a little safer, but there are many very valid reasons why business adoption is going to be slow at best.