Hmm...never realized there was "the list!"
My community: FearedGamers.net
Map suggestion/submission forum:
http://fearedgamers.net/forums/viewforum.php?f=38
We've been a long standing and close-knit bunch of gamers who just like to have fun. I.e. most of us don't play the game too seriously, but we always love to see good custom maps. I'm the guy in the community that takes in map suggestions and looks for new maps myself to put on our TF2 server. We currently run a mixture of 1/3 stock and 2/3 custom. Please feel free to send us any good maps (generally beta releases or higher) on our forums, or message me in Steam if I happen to be online.
We also do testing every Sunday at 9pm Eastern if any mapper would like to see their creation in action with 32 players.