As a mac user (12" Powerbook), YES! Get one! They may not be compatible with everything on the windows side of things, but most of the popular games are ported over. Even if you haven't used OS X before, you'll know how to use it as soon as you start messing around with it, it's that intuitive.
Everything works... it just works. Imagine plugging something in and it working, no drivers or anything
As for the LOL ONE BUTAN thing. With OS X you really don't need 2 buttons, you can do just about everything by dragging and dropping.... but if you really wanted to use a 2 button mouse, you could plug in one of your PC mice and use that (or get a mighty mouse
) Having only one button available also means software designers for OS X have to rethink everything to make it a little easier to use. No hidden right click menus!