Reason is simple....
Haha, Windows on Power PC.
Yes, the EA thing is big news. C&C 3, BF 2142, NFS: Carbon among others are coming to be Mac, which is a huge win for Apple fans. iD looks like they are amping up support as well. I still don't understand why EA couldn't bring those same games to Linux, but whatever.
The reason is quite simple: CORE ANIMATION 2! With Core 2 you can move around a room, pick up a book from a bookshelf, open and read every one of its 300 pages (photos incl,) etc. That's only the beginning! The room in the Harry Potter demo had over 20-gigabytes of info that was instantly available and usable to Core 2 users!
Core Animation 2 is a Mac ONLY thing, that makes game developing, etc. easy and extremely powerful and unique among other OS's! Those games will be available to Window users, but not with the same degree of cool graphics that are only available with Core 2. I don't think Apple will be making it available to Vista users.
Another reason EA is doing games for the Mac is that there is 60-million plus users, second only to Window's and growing faster than any other OS.
Business's run on facts, and the facts are that OS X is now at a point it can't be ignored by the business community.
Also, having a fully 64-bit system means that even though most programs in OS's are 32-bit, having Leopard means that if you do have a new program that needs 64-bit, you can run it natively without the need to log out of your 32-bit system, inorder to boot-up a 64-bit OS to just run one measly program!
With OS X Leopard you also get Windows Xp, Vista; Linux Sabayon, Ubuntu, Red Hat, Novell, etc. thrown in for nothing! From the 'ooohs, ahhs and wows, coming from the mouths of the developers at the WWDC, a third of which are new Window developers, I can't wait to see what some of the other 300 new aspects of Leopard will be?
It's a good time to be a MAC USER!