1. It's going to be Sci-Fi
2. It's going to be an MMOFPS.
3. Many former Bungie employe's are working on it with Blizzard.
4. It will be F2P
All three of these things were stated by the guy who runs mmo-champion. He has not been wrong about one thing Blizzard related in half a decade. I do not think he is wrong about this.
On a side note, 2013 is possible. mmo-champion first leaked information about Titan in 2007, with rumors dating back to 2006. 2013 would mean almost 7 years of development. It is very possible Titan is announced at Blizzcon this year, which many think it will be. Then released holiday 2013. If not Q1 2014. With a beta coming spring 2013.