I think, right now, it only gives you a small trumpet in the listing. And, there is not a widget to promote them. But, if implemented, it could give the purchaser something like a highlighting border, or colored background to highlight their ad. And with a widget it would allow the forum owner to feature paid ads in specified locations in their forum.
This could allow the forum owner the opportunity to have some income from some ads. I think depending on how many ads were running on the site, (I don't have many), I would start offering the featured at $5.00. When there seemed to be many more than necessary to fill a widget (the widget would probably display 4), then the site owner could consider increasing the price.
My small classifieds is picking up ads, so I am anxious to see a few developments like this one and the "renew ad". I had a major competitors classifieds on my site (with auctions etc.), but this one is much simpler and is attracting more users. I am an ex vb user and used to use Photopost Classifieds, it was very good, and I think this classifieds is on track! The few dollars I made from the Photopost Classifieds was done by charging $10.00 to unregistered classifieds users. There was a desire to have a system which would allow a registered user to have one (or whatever) ad running at any given time, free, but if a user wanted more ads, they had to pay. Photopost Classifieds was abandoned before this was completely smoothed out.