Community

The more popular the game is, the more money WotC will make from it and the more likely they'll be to keep putting out product.  Here are two places I've promoted it:

www.reddit.com/r/wargames/comments/zgdw6...

forums.somethingawful.com/showthread.php...

I'd appreciate upvotes on Reddit, and for everyone to help spread the word about this fantastic game to other communities on the internet!  Let's make Dungeon Command the next big thing!

I also made a similar post on BGG asking for more people to promote the game!  boardgamegeek.com/article/9993208#999320...

It's also not a horrible idea to promote it by just playing it in public, at your LGS before your MTG Tourny begins, or bringing two decks to a friends. Just being open and friendly when asked about the game, makes a massive difference between "That looks interesting" and "I'm gonna look that up when I get home."

Edit: Wrote two instead of to.