Both 2k and EA were negotiating for the NCAA License and both were likely to be awarded it, ensuring there would be both versions.
2k then balked at what NCAA was asking for and played chicken with the organization. They lost. EA remained in the bidding and paid NCAA for the license so they could continue their own series.
This is actually quite different from the NFL/Madden and MLB exclusivity deals. 2k could have remained in it (there was no bidding war for exclusive rights) but chose not to because they didn't feel the investment was worth it for them.
Here's the link from kotaku:
http://kotaku.com/344534/taketwo-college-hoops-talks-break-down/It's more than a year old, but it holds true. And I hate EA and love this game, but they really didn't do anything here.
"How would I characterize it? I would characterize it as it doesn't make a difference."
-- Derek Jeter