I feel misunderstood, may be I am not able to make myself clear. (That's because I am an Italian? ;)
I knew the Halo movement started before microsoft, because I was part of that, and I couldn't wait to see Halo running on my mac, as Jason Jones showed was possible to some macworld (was it macworld?)
That was the natural feeling, and at the time, you should remember, Halo WAS the natural follow-up to Marathon. Everybody felt that, Bungie as well. Halo was developed on a Mac and was going to be released as a Mac game for the Mac community.
But then something happened, and MS bought Bungie. From that moment on, everything changed. The launch of Halo was postponed of more than two years (if I correctly remember) the game was completely rewritten, this time for PC. And when MS decided to lauch its own game console, HAlo was chosen to be the flagship game to grant and to power the success of the Xbox. And the launch of the Xbox has been one of the most important marketing/advertising campaigns in history.
So, my friend, I am sorry to bother you with my words, but you should be aware that something dramatically changed during the developement of Halo, and this something is named Microsoft. That's why I say it again: "What I mean is that all this Halo movement was somehow ignited, being infact part of a complex, desk studied marketing campaign set up by microsoft/bungie" and I add "to launch the Xbox worldwide".
That's why I feel the whole Halo Movement, fandom, communities and whatever more, feel more like the result of a plan than the natural result of people's feelings. I don't think Halo fans are faking, but I think they are, in a way, victims of some Microsoft marketing manager who hired someone to create a viral marketing on line campaign, a community and everything else. While on the other hand nobody ever did that for Marathon.
BTW. I also feel this place is a bit like being with some very good friends, talking together and saying (most of the times) intelligent things...
