It's a desperate try to get more players. Tibia is dying at a faster rate than ever, just check the online counter from day to day and you'll easily notice it. They thought adding it to steam would bring them more attention, which it might have done for a short period of time, but it surely didn't last.
IMO, most of the new stuff they're adding to the map is pretty.."meh". Just check out Oramond, that place is just ridiculously mapped, kinda looks like they were in a hurry. Same shit with Roshamuul, most of that map looks very rushed as well.
My theory - They're trying to look as active as possible with adding new content, trying to get new and/or old players interested to squish out as much money as possible before the game totally falls into the steaming pile of shit it's been heading for the last 2-3 years.
It's not until now that I actually feel that the time I've spent with real tibia (about half of my life) is pretty much a waste, even if I did enjoy wasting it most of the time.