You should be able to dual boot, though it might be a little tricky on a Hackintosh so you will need to investigate that further.
As for the AMD support, no one really knows. Obviously Apple only includes support for hardware it includes in its own units, so my guess would be you need to wait until Apple gets around to including a 7xxx series card, then someone needs to tinker with that kext (driver) to try and make it work with other hardware.
As for the wifi support, OS X tends to only support Apple's wifi cards, so I would look for something else that claims to support OS X.
Just kind of in general, making a Hackintosh is a lot of work, and it is pretty much always going to be defined by a series of tradeoffs. It is not like you can just slap together some hardware and you have an instant Hackintosh. You have to be very careful with the hardware selection, and even then not everything will necessarily work 100%. Just based on the questions you were asking, you may want to think kind of long and hard about whether or not this is something you want to pursue. If you've ever installed Linux, you probably have some idea of the sometimes spotty hardware support, only where Linux has a fair amount of attention from the major hardware players, the Hackintosh community really doesn't. It is very similar to the earlier days of Linux, where it was just a handful of people trying to cobble together some solution for whatever hardware they happened to have. Is this something you're prepared for?
@ cl-scott: No this is not what I am prepared for. I think it would be the best choice not to build a Hackintosh as I can buy one when I am entering university in a year in order to do work and video editing.
@ daship: I see. Like my response with cl-scott, I will not make a Hackintosh. I was only thinking of that for video editing (Final Cut Pro). But I will make a Win7 PC in Oct with the new AMD Piledriver then.