According to UFC president Dana White, it looks like we're going to be seeing a lot more fights on TV and no more on Facebook as soon as the Fox deal kicks in. He said this a month ago, right after the deal went down, but it seemed to not register with anyone at the time. Here is a link to the interview (the Facebook stuff starts at the 3:36 mark), and here's what Dana had to say about it.

 As much as hardcore fans love the idea of the fights streaming on Facebook, it's absolutely better for everyone involved to get them on live TV. The undercard fighters will receive much more exposure, make more money from sponsorship deals, and fans won't have to worry about a possible dodgy stream. It is currently unknown where they'll be aired (my guess would be Fuel), and it will obviously lead to the UFC re-shaping the way they show TV prelims. Will there still be a one-hour main episode with two top fights, like they currently do on Spike TV? Will that air on the same channel as the other prelims? We'll have to wait a while to find out, but it should be interesting.