1) Profitability: I wonder how profitable and sustainable this is for Google? They can subsidize it for only so long before deciding to discontinue it as has been happening to many of their services recently.
2) With Google as your ISP and TV channel provider, they will have the potential to know everything about you, probably even more than you know about yourself! Imagine you use all their services, they will know about your surfing habits(via ISP, Google searches and clicks, G+ buttons, Google ads, Google analytics etc.), your location(Android location services/GPS. Google Maps), TV channel viewing habits, Gmail, social network(Google+), phone calls(Google voice), etc. etc. It will also provide malicious and state actors with a one stop shop to steal/request information from.