Well as you can see now Halo Reach is out and lacking maps, yes dlc will be soon but I reckon we should forward this idea I have (No doubt others have thought of this but yeah). What I propose is bungie make a competition for the best community map/maps, I was thinking invasion orientated being as there are a lack of maps in that section. They play and test and throw out the final few maps in a double exp weekend community map playlist, the 1-2 out of the few that have been selected that was picked the most go into the invasion playlist permanently. I know they wouldn't do this any time soon because they have issues to resolve but in the future this in my opinion would be an awesome idea =D
It would be kind of a waste to setup up competitions like that. Forums dedicated to forging can host competitions and decide winners themselves so all bungie employees would have to do look through the winning submissions and decide if the maps are worthy or not for matchmaking. Plus they don't have time to go through one by and test each submission thats submitted because there would be thousands of maps to go through (most of which would be crap). There is also the addition of the in game file searching which has a top rated and top recommended (or whatever the hell they are). Bungie can also look through these lists and see which ones are suitable for matchmaking.