Hollywoods allready trying to "cook something" with the Halo idea and there are rumors of Peter Jacksons involvement. These are just rumors.
I dont know,games transition to film are mostly dull,with few exception. For example,I hope they never ever make a Half Life film,unless its gonna be a big budget miniseries,like "Band Of Brothers"....
On the other hand,I am eagerly looking forward to the Bioshsock film,wich is allready in production. If they mess that one up,I will never forgive Hollywood.