Thanks, Jet, but Harican got there a long time before you did - and your pack is about to become outdated, with the addition of the Halo 4 Modeller's Asset Pack, which contains models not currently present in the initial wave of files. I appreciate the effort and sentiment, but I'd ask that multiple 'packs' not be made available. This will help prevent confusion from having multiple 'packs' online at once, each with different files in them. One comprehensive pack is all we need.
I shall have the Modeller's Pack online soon - look out for an edit to this and my original post for more information.
EDIT: the Halo 4 Modeller's Pack has been uploaded. Please find a link added to the OP, or you can simply find the file HERE.
EDIT V2: I've noticed that a lot of people are going ahead and unfolding these files as-is, directly from the files I've posted. PLEASE bear in mind that these files are provided IN RAW FORMAT, and as such, may contain issues such as open edges and come superfluous geometry. It is HIGHLY RECOMMENDED that these files be refined before unfolding them, as opposed to simply taking and unfolding them as-is.
If there's any interest, I'm also willing to put together a Halo 4 Weapons and a Halo 4 Extras pack for those that would like to have them. The Extras pack will contain supplementary files, such as the Armour Abilities, AI chip and Multiplayer-specific items, while the Weapons pack will contain a comprehensive database of Halo 4 weaponry, along with alternate skin designs for reference.
The weapons and extras pack too? Wow that would be super awesome!!!