Besides looking at the base tools and studio popularity, it's also helpful to research the ecosystem around the software. What are schools using? AM, iAnimate, and AnimSchool all provide rigs in Maya (though the latter may also provide XSI equivalents?). Who's writing helpful scripts/plugins and for what software? On the…
thatanimator maya has had python for a long time now, a lot of it;s legacy stuff is mel of course, but most new scripts are in python using either the pymel moduals or the cmds ones.