I don't know when they flipped the switch, but Cortana definitely didn't let you add a college football team under interests>sports at the beginning of the season! This makes me very happy! Fight on USC Trojans!
This was the best feature of Cortana so far for me. Was so disappointed when I first got her and couldn't find my team.
That being said the interface is great, can just open up Cortana and she'll say when and where the next game is, along with previous game score. I love it!