I know that one of the main areas where our beta here is lacking is questions per day (and possibly correlated, visits per day). At the time that this similar question was asked, apparently the site's shrinking QPD was a concern, and back then it was 8.6. Around a month ago, it was 4.1 and today, it's at 3.9. Have we perhaps all but saturated the well of Japanese knowledge? Are we all out of good questions? Anyone, please share your thoughts.
"Have we perhaps all but saturated the well of Japanese knowledge? Are we all out of good questions?" - no and no
Let's deal with "How to improve the site's qpd?"
"Questions per day" is a secondary stat off of two things: "exposure of the site's members to Japanese" and "number of site members visiting regularly".
I know that personally, my low question count is a direct result of a tight development schedule for the last year... interfering with my ability to study as I'd like. I can't really speak for anyone else, but I find I have a new question at least once or twice a day when actively studying.
We have a few things causing us problems for increasing our visitors.
SEO is really, really hard for Japanese language-related questions. Kana/kanji/multiple-romaji writing systems prevent most questions from coming up near the top. There are also some incredibly crappy sites out there with ridiculously high page-rank for "Japanese language". I'm not sure what the solution to this is... but it's probably going to involve a bit of research into "how are people most likely to ask 'why is を used with 行く?'" on a search engine, and then seeing if we can tweak titles to match the most popular question forms.
In lieu of the above, one approach I've taken to with some success is plain old redirection. I'm a member of three other online Japanese-study communities, and I'll filter my answers on those communities into three buckets.
In the rare case where someone here hasn't asked the question, I should probably be better at stealing (and rewording) the question.
This has worked reasonably well... I tend to get very positive responses and hopefully a few new users for JLU. (as well as providing link-bait for search engines)
I tend to ask more questions in chat these days, because I'm less likely to receive downvotes or criticism there than on the main website.
I am not technical but it seems that "Japanese Language and Usage" does not get picked up by people searching a site like this: