After Effect CS 6 on Imac?

Hi guys,
I just saw the new features of AE CS6 and, lucky me, I was the ass sat on my chair so I didn't fell down. We finally have 3D text, XML import and, last but not least, camera tracker

But ... I bought an Imac last year and I wonder if the 3D raytracer from AE will be supported by my graphic card. Does anyone knows if it'll work with the standard Imac card? And, if not, if I can change the graphic card on an Imac ???

Thanx

Marc