Originally posted by another user
A very good and anonymous source tells us that Halo 4 is already in full development over at Bungie. I wish to God She/He/It had more details to share but at this point all She/He/It can confirm for sure is that Halo 4 is an official project being developed by Bungie, at this very moment.
With more than 20 million copies of Halo 3 sold worldwide, I know it’s a no-brainer that the series would continue somehow. It’s nice to get this sort of reassurance from a source who has never been wrong for us before.
If we get more details, we’ll share them. If She/He/It is wrong… They’ll be quietly disposed of.