There's a Halo movie in the works. Yes, another one.
This one is sees Ridley Scott as executive producer, with Battlestar Galactica director Sergio Mimica-Gezzan on board as well. The series is expect to follow the same format as what Machinima did with Halo 4: Forward Unto Dawn, but this will be following a surgically-enhanced super soldier that's not Master Chief.
We'll be learning more about whatever this is at E3. And this is totally different than whatever it is that Steven Spielberg is working on too.
I am ALL for anything Halo, but the more we hear about stuff like this, the more I fear we're not actually going to get Halo 5 this year. Instead it's just filler until the next entry in the series finally arrives. I hope I'm totally wrong.