I think that theymos analyzes
[1] the success of the pumping algorithm and will be generalized to all Marketplace boards.
So I think the solution to this problem(Bumping Spam) will be soon.
Also, if the rules of the forum are properly understood, "some solutions, such as the welcome message," will reduce spam due to the difficulty of scam.
Generally, marketplace boards need a lot of extra special rules and some real changes.
[1]
Bounties (Altcoins) is added to the targeted boards. For other busy marketplace boards such as Digital goods, I'd like to wait a while and see how this goes, but they are possible later additions. For local boards, local mods can PM me to request that the boards be added to the list if the first page of the board is always full of topics with a last-posted-in of today.