PC v Mac games

I'm obviously ignorant about this subject, but is it difficult turning a PC game into a Mac game.  Is it the cost that keeps companies from making games available across both computers?  Blizzard and a few other companies do it, and especially now with Steam support for Mac, I would hope that more games become available for Mac.  There are so many games, like Mount and Blade that I would love to play, but I have neither the money or the interest to create a gaming PC.

bootcamp

The hassle for developers is to release games on macs since they are like 5% of the computer market. If your using bootcamp, your essentially using a computer with windows to play games, except you don't have the best components for gaming. For what you paid, you could of got a really good gaming pc and if you want, you could of actually installed mac and windows on it even though that's rare anyone will install osx on their pc's.   
 

http://www.netmarketshare.com/operating-system-market-share.aspx?qprid=8    

My friend uses bootcamp on his MAC. It was sort of a hassle getting it started, but it's fine now he just boots it up like a PC with Windows. What sucked at first was his lack of HD space since he had to partition it between OSX and Windows, but he just got an external HD. Now the problem is he has the best MAC laptop pro thing, but he can't play all of the games out now since he's bottlenecked with the specs an un upgradable MAC has.

Actually, it's pretty simple. Most games today are DirectX based, and that is a Microsoft product. Why? Honestly, mostly Microsoft propaganda. Most of the stuff you can do in DirectX can be done in OpenGL. Companies like Valve and... others can easily (well, relatively) port their games to Mac since they're based on OpenGL.

" Actually, it's pretty simple. Most games today are DirectX based, and that is a Microsoft product. Why? Honestly, mostly Microsoft propaganda. Most of the stuff you can do in DirectX can be done in OpenGL. Companies like Valve and... others can easily (well, relatively) port their games to Mac since they're based on OpenGL. "

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