So yeah, I loved UO. Because I got real emotion from playing it. WoW is so stripped of highs and lows, that it really doesn't matter.. like in Equillibrium. You can't take away the extreme sadness without removing the potential for great joy. And stomping a pk or two that made your life miserable early on was truly rewarding.
Anytime somebody wants bad enough to accomplish something, they will. The real thing protecting Apple and Linux... lack of market share. The pros don't target bums for the big heist. If you you are going to put effort into something, you do it for the returns, and writing a devastating linux/mac malware (when linux varieties are far less standardized than MS OS's, and mac has 80%+ less market share) just isn't going to get you the attention/money etc. that tampering with the market share leader will accomplish.