For the past couple of years Ad Age has had an editorial partnership with TVGuide.com focused on its Watchlist, a customizable entertainment guide that lets users make a list of their favorite shows, actors, etc. We're interested in Watchlist because each season the top 10 most Watchlisted new shows tend to have a high probability (up to 80%) of being picked up for full seasons.
For its users, Watchlist is a great service that lets them plan their TV viewing; for us, it's a sort of massive focus group of informed TV fans (the database of registered users hit 2 million earlier this summer). There's a "wisdom of the crowds" thing going on here.
A caveat we repeat every time: Keep in mind that Watchlist users are, essentially, publicly expressing hope that these shows will live up to hype -- as well as an intent to watch. Series that exhibit early promise and score full-season orders can and do, of course, still end up getting canceled later on (as storylines run out of steam, as networks stick good shows in bad time slots, etc.).