I think you should schedule an "Official TF2Maps.net MapPack" release...say June. Between now and then (and this is the contest part), 5 maps will be chosen that will go in the "official" pack. The release of the Official Pack, will be news of sorts, and we'd distribute it to the server runner people, and try and get some blurbs on gaming websites and such.
Contest entries must be finalized (no B's or RC's even) by May 1. As of May 1, set up a popularity contest voting area, and advertise that...try to get people to play the maps and vote.
One entry per person, so Youme would have to decide if he wanted to submit hoodoo, halfacre, or whatever (though I see no reason people can't use old maps that haven't been released in any kind of official capacity elsewhere).