I like the idea of this forum. It's great.
One promotional idea would be to buy a banner in places like The Womb (http://thewombforums.com/
), Gearslutz (http://www.gearslutz.com/board/
) and REP (http://recforums.prosoundweb.com/
). At The Womb, they sell (or used to) sell really cheap small stamp-type banners.
Especially The Womb has had similar stuff going on for years, The CAPE and MixIt!, a lot of people would be interested in this.
Promoting in the aforementioned places will probably attract a lot of professional mixers (such as myself), which is likely to raise the overall quality of the mixes (?), but may lead to all sorts of pissing contests and gear-wanky stuff.
Also, from my point of view an "Mixer for hire"-kind of section would be quite nice for us who work in the field proffessionally. It would be a good way to make a distinction between the projects that are purely for fun and those that are commercial projects in need of a mixer, that would serve both parties nicely. Obviously, the ideal would be for the pros to mix a couple of tracks from the forums and use them as "CV"-type of tracks here instead of just listing commercial projects they've been involved with. But I would like to see that as a separate section, it would make more sense to me.
BTW, apart from mixing I also teach mixing and engineering and I was wondering if projects here could be used as educational material? It would be wonderful to give a wider variety of styles for the students to mix than what I can gather from my own vast, but indie/rock/jazz-filled archives. If they're licensed Creative Commons, wouldn't that make them available for educational use? Are there licensing guidelines or rules visible here at the forums? I didn't spot them yet anyway... That would be an important thing to emphasize, as that would clear any copyright issues.
But as said, I really like the idea of this place!