When Unix-like goes so far as to include windows with MSys, what does it exclude? And, for windows users that don't like to type, there's tortoisegit (http://code.google.com/p/tortoisegit/), which appears to be generally functional.
Mercurial is still better supported under Windows. Anecdotal evidence: compare the Eclipse plug-ins (under Windows) for git and hg. (And before there's flak about Eclipse: it is a widely used tool, under Windows at least).