I think it's very important not to get caught up in semantics with this. It doesn't matter what you call it: marketing, promotion, telling your friends, posting on forums -- it's all essentially the same thing. As mouser said, you can't survive without other people knowing about you and what you're doing.
What we're really discussing is the balance, and that's the reason people lean toward "promotion" over "marketing", or another term over some other term: each term carries a preconceived idea of the balance between the marketing bit and the other bit (whatever it is that you do).
Our other bit, as zane said, for DC includes:
There are lots of assets, but they start with developers and members. Among the software offered, the contests, the free-wheeling discussions, the software discounts
-zridling
This is why we're here. As mouser said, if we lose our focus on these things we lose the reason for our dc community. But if we don't have some sort of marketing/promotion/sharing the joy we'll lose the dc community too. Any closed community is doomed, but we're not closed... we have crawlers indexing our site that will come up in web searches. The question about that (passive) marketing/promotion/allowing people to find us is, is it achieving what we need; or is something more required?
Reflecting on what you're doing and how successful it has been is a worthwhile exercise, and I welcome zane's question. It may not be the best subject for general discussion though.