Like hundreds of traditionally minded enterpriseIT cousins this guy is not doing his homework. What he really wants you to read is this...
If you get the OSX/Tiger thing going the clients will get the idea and power to be more than the lemmings you currently control with your networks. They may wish for more than MSOffice and loads of games that they can mindlessly operate. They are going to want to use multimedia, maybe even create it. Then you'll get those Macintosh artists that will scan pictures of their butts and clog your mailbox account with Hi Definition streams of crap. At least the reds and oranges would be richer.
Your mindset speaks of IBM and HP relationships, my mindset welcomes to video colors like deep red and saturated orange. So while you go off worrying about the network of viruses, I'll pay extra for one that is free, secure and about the front-end aka the client. Oh yes... I like the colors!
Perhaps you could wake up and see that Steve Jobs has created a two year headstart and is building it to three. Apple's plans with Sony and Unix and opensource development combine well with deployed H264. Deployed to your cell phone if you like.
You are correct in saying that the place for you is in Windows, I think it is the smartest thing you have written. I and possibly a lot of posters here would rather you didn't wake up.