IW don't have any plans at the moment of making Call of Duty: Modern Warfare 2 playable on mac-computers.
It is already out.
It came out in November 2009
April 30th
5th of may X D
you can illegally download it for PC, Mac, or xbox360 using a torrent site. I recommend the Pirate Bay (thepiratebay.org)
You have to have a mac first of all then you need to get windows xp on it and then put bootcamp on the mac. After you have done all that put a thumb drive in your PS3 and put your MW2 Data (saved data) on to the thumb drive then take it out and put in into your mac and download Hackforyou at ihack4u.com and then upload your data onto the app and then ihackforyou will change the data to 70 prestige 10 and then put the new data onto your thumb drive and then delete the old data and put the new data on your PS3 and you have hacked mw2!
I heard the end of this month i think it was confirmed. So start saving :)
There is going to be a sequel, which is supposed to be coming out in 2011. The official release date is unknown, but the time period is supposed to be about a popular character in the mw2 campaign, Ghost, and it is about how he became ghost.
Didn't Bernie Mac Die?
Simcity 5 will be coming out for the Mac on 29 August 2013. However, the release date might be delayed.
The call of duty coming out for the wii isn't exactly MW2 but it is a special call of duty made just for the wii.
Steam will be available for the Mac sometime in April (See links below).