Does the "Intel C++ Studio XE 2011 for Windows and Linux" supports ATOM
Yes, the same compilers are recommended for Atom as for other CPU types. It was recommended to us to use the plain SSE3 options (/arch:SSE3 and the like). I'm not certain which choice would be made by /Qxhost. There is a special SSE3 option for Atom, but we were informed that efforts are made on both the hardware and software side to make the plain SSE3 work as well (and support running on other SSE3 CPUs).