I don't think the developers of Fav.tv intended this to be a second screen app. The app seems to be developed more as a digital assistant-type app, reminding you when you favorite shows are on. Essentially, you tell it what shows you like (and who your Live TV provider is during registration) and it tells you when the show is next on (alerts you if you like). It also has a news feature which can be filtered by your favorite shows which is interesting, but all of these features seem like something that will soon be added to other apps (IntoNow, Fanhattan, zeebox) vs. something substantial enough for a stand alone experience.
Simple. No ability to control the first screen. None.
Social. You can "check-in", but there is no integration with Facebook or Twitter, only Fav.tv friends. Very low.
Seamless. No integration of content sources other than your stated live TV provider feed. None.
Stimulating. I am not sure the news feature really counts here. Very low.
Discovery. While there is constantly the "opportunity" to see featured shows presented to you, that is not really a Discovery capability. None.