I can't say positively, as I have never used Boot Camp or any Mac OS for that matter, but I'm pretty sure it will work. The System Builder version is only different in that you don't get full support from Microsoft, as far as I know. So, it is a full version and as long as you can install Windows 8 with Boot Camp, which Apple's support pages say you can, then it should work. Good luck.
Sure can, that's what I'm using it for. The only issue I had is the boot camp drivers that you are supposed to install after windows 8 is done installing caused Windows 8 to crash. So I just didn't install the bootcamp drivers. Windows 8 really doesn't seem to need them anyway.
I really don't know Apple systems well enough to answer but with the release of Boot Camp 5.0 for OS X Mountain Lion version 10.8.3, only 64-bit versions of Windows 7 and Windows 8 are officially supported. Hope that helps.