Apple provides bootcamp as a convenience. They probably don't see a need to have HR head hunting for killer windows driver developers. They probably want you on the mac os side more and focus efforts there.
You will also find this is not an apply only thing. When switching vendors at some point you can and will enter support grey areas. We for example switched SAN vendors a bit back. No help from the people we were leaving (support didn't cover migrations from them) and while of some help the new SAN vendor can only do so much (they can't hire experts to cover all SAN flavors and, well, thier experts are supposed to be trained heavily on their systems).
Also did your install have any custom flavor you put in it. I and others I know with basically vanilla installs have gotten better temps after. Would you be running any special apps as well? I know for one or 2 games I play my temps were much better in bootcamp than in the the mac os run as ports (same game, jsut mac had it in a wrapper, which I know add processing overhead and therefore heat).