Shouldn't college also be OS agnostic? If just teaching Unix/Linux or Windows is the only exposure, aren't the students being cheated out of what is done with programing languages? ZOS, OpenVMS, NONSTOP, SCOPE (on a CDC CYBER I think...), OSX, and some others I've touched that I don't remember, where all different results to some common problems: how programers and users utilizes resources to get work done.