Dont think they implemented anything, they just restricted character creation on a lot of servers. It'll be back (if not twice as bad) when the servers go up again.

I dont see the point to ingame advertisement though, if anyone wanted to use a RMT service, simply consulting google would be much quicker and easier.
It's not like anyone has ever been tempted by ingame spam like that, certainly not swayed their intent to buy or not to buy anything :/