I just thought I'd leave my input on this discussion.
I'm a writer for Inside Mac Games so I've got a lot of experience with the front end of Mac games, as well as the workings behind them. I think the Mac platform is an excellent vehicle for gaming, although it is often misunderstood.
As far as I see it, the main problem with the Mac gaming market is the perception that all innovation comes from the PC side of things. People look at the latest Battlefield 2 movies over on PC systems, then load up the 2 year old mac port of Battlefield 1942 on their top-end G5 and cry. If people keep using the age old adage "Macs aren't for playing games", nothing will change.
As the Mac stands, it is an excellent platform for independent and innovative game development. The tight integration with OpenGL, excellent support for Altivec, Dual Processors and the possibility of 64 bit, along with the excellent relationship between ATI, nVIDIA, Apple and nearly every game porting/dev house out there shows great potential. 90% of the time when a Mac game runs slower than a PC game, it's down to proprietary decisions by guys over on the PC side. You just have to look at the Quake 3 port. This was an excellent example of a cross platform game done well. At first release the game was slightly slower on Macs compared to equivalent PCs. The game got worked on by OS X friendly guys, and in it's present state no PC can come close to a top end G5 running this game. Dual processor support and Altivec has been implemented. Hopefully this OpenGL news will bring speedier deliveries to OS X ports.
In terms of talent, the Mac has more than it's fair share of excellent game developers. People like Brad Oliver and Ryan Gordon go out of their way to bring popular or interesting games to OS X. You only have to look at the recent OS X port of the free game, Enemy Territory. If you look on the credits list for the OS X port, ONE GUY is listed amongst a sea of PC programmers.
If people just went out looking for games, they'd find the Mac is a goldmine. There are so many excellent games that have little publicity it's nearly a crime. A good example of a obscure game getting rare publishing/publicity is Kill Dr. Cote. A uDev Games entry a while ago that recently got made into a commercial game by Freeverse. The Mac has a good deal of influence in the gaming world. You just have to look at Bungie. In their time as a Mac exclusive publisher they made classics like Myth, Marathon and Oni. I still play all three of these game series on a regular basis in arranged games. Could you necessarily say that you play nearly every game from a PC exclusive house upto 6 years after each game was made?
Sorry if I ranted a lot, but I get sick and tired of hearing my work in the Mac gaming industry is a waste of time. By the way, I also own an Xbox. (Halo 2 kicks ass

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