Sometimes I see an ad coming up on the site, but I'm in the middle of logging, reading an article, or some other activity that has my mind engaged - I don't want to break my thought but I'm interested. Or sometimes days later, I think, "what was that about", but can't remember the seller's name.
How about adding a current advertiser tab under SHOP, where you could look at all the ads currently running on Spark. In my opinion, would even be more helpful, if it allow a comment section for people that actually had used the products. For example, saw some cool exercise pants, but wondered about their fit in a bigger size.