Hey, have a look at this, Nitrousoxide has been at it with Microsoft and Gearbox to try and know more on the release date of HEK, this is what he wrote:
I, as a dedicated modder, as becomming fed up with the wait and the bullcrap, as are many others. I decided to place a few phone calls (again) and really try for some information, regardless the cost in long distance calls.
I called Microsoft Games tech hotline, they directed me here, there, everywhere. Every number they sent me to never even heard of the 'Halo PC editting kit/tools' and had no information in their databases whatsoever. I called every single department in Microsoft that would pertain to either games, development or pre-release testing. Not one person had one stich of information about it, or ever even heard of it. I must have called 20 diffrent phone numbers, sent thousands of emails, and even directly chatted with a technician. Nobody knew anything. Heck, they even directed me to Randy Pitchford's desk!!!! I directly spoke to Randy Pitchford himself and he specifically said "We have no information about it, as soon as we recieve any info we will make it public.".
Can someone PLEASE tell me why the heck nobody at Microsoft has ever even heard of the Halo editting kit, why Gearbox can't say a word about it, and why there is absolutley NOTHING about it in Microsoft's information databases? Even if you go onto their site and search for things like 'Halo kit, Sapien, HEK, Halo editting kit, Halo edit, etc..' you get nothing!! Nothing saying 'pending release' or anything.
I would also like to know why HellFace said that "It is finally in Microsoft testing" two times, about a month apart. Things like this make one wonder.
Okay, the HEK definately exists, due to Cortana's screenshots, but does Microsoft have any intention of releasing it? I must say, I'm beginning to become worried. Myself, I will be very dissapointed that I cannot accomplish the things that I want to with my mods, but I especially will feel bad for people like Mrs. DoubleFire who have worked especially hard on things that are useless without the HEK. It's just not fair.
Also, some people say that Microsoft may be holding the HEK as not to steal any thunder from Halo 2. Well, if you think about it, the longer they hold onto it, the longer it's going to take for us to 'get over' it, therefore, they are cutting down on Halo 2's thunder ever so slightly every minute they hold onto it. No doubt that Halo 2 will make us all drop Halo PC like hot pennies (for a while, at least), but c'mon, Microsoft isn't playing the game (no pun intended) smart here. Also, if they don't release it at all, it's going to take some time, but people are likely to develop equal functioning tools, and those tools will be released to the public closer to the release of Halo 2, therefore, even more thunder stolen from their beloved Halo sequel.
Maybe it's just my anger/anticipation talking, but I know I'm not the only one who feels this way. I know that this is probably the 1,000th HEK post, but the people have to know how no matter who you call or speak to, they either never even heard of the HEK, or can say a word about it. This is not fair. We all paid our $50. We deserve some answers.
Now, as far as what we can do about this, is yet to be determined. From the looks of it, it may be up to dedicated people like us to save Halo as we know it. Gearbox has a history of porting games that suddenly 'become forgotten'. It's not Gearbox's fault, but the people who hold their leashes. They suddenly tell them 'not to support the game any further'. Halo PC very well may be headed this way, and is way too good of a game to be let go so easily. Something must be done. We need fricking answers. Now.
Please, join us. Write letters. Place phone calls. Post in forums. GO THERE if you can make it for Pete's sake!! We, as the Halo community, who paid our hard earned money for this game do not deserve to be ignored, and demand some answers now! Make with the HEK!!!
(Original topic found at halo-mods.com, under Open Carnage)
So yeah, right after this post will be up, I'll be signing the petition too.

*edit*
Thats it, Im signer number 853 (or smthg like that)