A:
Yes, Chromecast added this feature last year. I have not personally tried it as i got rid of cable all-together. Here is an article:
http://hometheaterreview.com/chromecast-gets-xfinity-tv-go/
Also, chomecast has a new feature in beta, screencast, where you can just cast anything on your mobile device's screen to your TV; so whatever is showing on your device's screen will also be on the TV.