Housing! It’s fashionable, it’s fun, it’s extensive, it gives your character in a given game a place to spend time other than milling around the auction house. Housing in MMOs is a fun thing, and the MOP writers and readers are generally pretty enthusiastically pro-housing. But there are still a lot of different tiers of housing, lots of different options, and a whole lot to consider about housing beyond simply asking if a game does or does not feature a housing system.
Some housing systems are developed and robust enough to serve as a game in and of themselves, with plenty of chance to earn furnishings through gameplay and a developed market for same. Others are… well, more perfunctory, a matter of having a space that isn’t necessarily all that developed. And some people are perfectly happy with that, having a house of some kind even if you can’t do elaborate decoration. So how much effort do you want to put into MMO housing? Would you rather have it be vital and developed, or very optional and pretty feature-light?