Bronco,
Open GL is just a GRAPHICS API. Even though AH used OGL for graphics you still have to rewrite the rest of the game engine for Mac. Just like you "Mac guys" to try and oversimplify things

Btw all you "Mac guys" complaining about pc:s beeing hard to configure and "downtime", this is the downside about having a configurable and open architecture as opposed to Apple. If you don't know how to configure your system or install software and hardware properly you obviously is going to have a defunct system.
I'd choose the the configurability of the PC any day over the Mac's idiot proof OS where you are limited to what the programmers allows you to do. But that's just my opinion. If you don't like "getting under the hood" of you machine and getting you fingers dirty I guess the Mac is an alternative if you can afford it and stand the lack of software.
I think the comparison with cars is quite good:
Mac: Japanese sports car, expensive and new design, no problems to get to run, just turn the key. Great around some bends but a bit boring to drive in the long run. Looks the same as any other car and not a lot of accessories.
PC: Muscle car, cheap to buy and old design but a lot of power. Requires a bit of skill to get to run properly but a lot more rewarding when it does. Lot's of accessories to personalize you car after you needs.
//dance-