I do not see myself exactly as a computer newbie.
I'm using A pc as we speak, I'm just waiting for my powermac g5 to arrive.
I am going to make the switch for the following reasons:
The looks (love it)
The security (not as many bugs and spyware)
I'm not really buying a mac for gaming, but there are a couple of new games to run on the mac, doom 3 is coming and world of warcraft is also being brought to the mac.
You can always make a dual boot system with yellowdog linux and runCedega
As for the native one button mouse environment, press control and the mouse button and you hit the 2nd mouse button.
Or you can always buy a logitech mouse with 2 buttons (It works)