It's in professional. I've used it myself in pro 32 bit before I installed enterprise (which also has it).
{Edit} Just a little bit of a backup:
http://www.microsoft.com/windows/windows-7/compare/default.aspx
{Edit # 2}
Didn't see Grant's edit. My bad man.
{Edit} Just a little bit of a backup:
http://www.microsoft.com/windows/windows-7/compare/default.aspx
{Edit # 2}
Didn't see Grant's edit. My bad man.