I don’t see why this should be too early to talk about it already now…
I think we can expect many map(packs) and other custom stuff for BM, after it’s release (especially for co-op and dm).
That’s why I think it would be a good idea to establish a kind of search database on the main page, where registered users can add an entry to their work in the category map/mappack -> singleplayer/deathmatch/co-op with a description, preview images and links.