From your link, a further link doesn't make it sound great at SO - 2-4x the utter failure. But they are very positive about it because the cost of implementation was very low. Just top-level posts or no geolocating would be even cheaper.
You may be amused (or something) by this search
A possibly relevant data point: I usually post any links to books I put online with my amazon affiliate link and in the last 3 months I've had around 25 clicks from links to books I believe I posted in Less Wrong comments and no conversions.
To whom it may concern:
This thread is for the discussion of Less Wrong topics that have not appeared in recent posts. If a discussion gets unwieldy, celebrate by turning it into a top-level post.
(After the critical success of part II, and the strong box office sales of part III in spite of mixed reviews, will part IV finally see the June Open Thread jump the shark?)