From a SvN comment by Jason:

"We’ve advertised here and there, but all things considered the number would round down to zero. We’re currently advertising Highrise on The Deck, for example.

I don’t have anything against advertising, but we’ve found better ways to get our message out than spending money on advertisements.

I like what Amazon.com does: Instead of advertising they give their ad budget back to their customers in the form of free shipping."