OnLive works fine. You have to remember a few things though. First of all, 100Mbps is a stupidly high estimation for video. Plus people are generally fine with 720p if their internet can't handle it. Also most people can't really quantify input lag or just straight-up don't notice its effects. Thus, with fast encoding and a low physical distance to servers, streaming games works fairly well for most consumers.
I could never do it though, I hate input lag so much that almost all my displays are CRTs. (1080p projection displays woooo)