I've just had about 20 old topics suddenly appear again on my watchlist after being necrobumped by these spammers. Searching for "Coins rise 200%" in the last 1 day is giving >400 results at the moment, and that's even with the ban hammer going strong:
I'm reporting loads of them, but the easiest thing at this point is probably for a mod/patroller to go through every account between #2610000 and #2620000 and nuke everyone with a name that ends in an underscore followed by 2 characters.