There are no confirmed reports as of now, but I've noticed that Alex Proyas (I, Robot , The Crow, Dark City) might be directing the Halo movie.  I for one have only seen I, Robot out of all of Proyas works, which I did enjoy and it seems that most of his movies have gotten good scores/reviews, so if he is choosen as the director I think that Halo might be heading in a good direction.  Again, this is unconfirmed and I just came across this info, but what do you think?

Source: imdb.com