I thought I'd quickly share a data point for hackers around here trying to hit a spot on Product Hunt.

I reached #6 and 136 upvotes on Nov 3rd with HN Cards (http://www.producthunt.com/posts/hn-cards), and over the past 10 days this has brought just short of 500 downloads for the app (which is free).

The most important benefit for me was the feedback received (either on PH or by email) and corresponding product validation. The number of downloads is clearly not impressive, but still very decent.

Hope this helps!