In my new role as Mac zealot...
Far be it from me to get into any sort of flamewar-causing religious-type discussion (ha ha), but pcolijn asked how any sensible developer could use a Mac for their work, given a few of its flaws. In order, and without any actual reference to the questions:
I don't watch movies while computing, because I can only do one thing at a time. I know, I'm an inferior life form. Sorry.
I don't play movies on my computer at all, actually, because computers are stupid. (It took me years to find the root cause of my endless video-playing problems on every operating system, but that's definitely it.)
I prefer to listen to my CDs rather than looking at them.
And last but certainly not least...
- I use ion for my window management, of course! It's just as excellent as ever, plus power management works. Actually I had to upgrade to ion2 (I was probably the last person in the universe to do so) in order for it to make sense. In ion1 the results when you press F9 are hilarious (all the frames are separate windows and swoosh to random locations) but rather useless. Anyone who wants a copy of my ion2 config files, just ask.
Also, because you didn't ask, I have no patience for the actual OS X "imitation Linux" crap (any OS released post-y2k where just typing "find" doesn't list all your files is stupid, plus "ps axr" doesn't work, and fink seems to mostly consist of non-working packages) and installed Ubuntu in a virtual machine. So I'm "remote displaying" on my MacOS X Xserver from my virtual machine. It's a bit silly, but due the magic of modern virtualization and disturbingly fast CPUs, it works fine.
(How fine? Well, pphaneuf asked me to time how long it takes to compile Quadra on native OSX vs. my virtual Ubuntu, but unfortunately I'm not smart enough to compile it on either one successfully. Anyway, it's fast enough for me.)
ssh+2FA to all your machines, anywhere, without opening firewall ports.