One idea may be to participate on other translation forums and bring them to here. You see a good question on another site, you put it here, you answer it, and you provide a brief description on the other site. Note that in order to comply with nettiquette, you should:

1. Not copy the answer from another site (it would be best if the question weren't, either)

2. Provide at least part of the answer on the original site

Posting on Hacker News has been positive, that's where I come from, so posting on similar forums might work, too.

On another level, the site should be multilingual at some point in the future to appeal to a broader audience of non-English people. Members can collaborate to translate the site into other languages.

Just my two cents.