Since you also mentioned online roleplaying, I'll say Everquest 2 has the best player housing there is. Carpentry is one of the professions and they can make anything for the house. It is seriously fantastic. You start out with a studio but you can have anything from a normal house to a mansion to a boathouse, I think even an airship.
I've played quite a few online games and have never found the quality of housing as there is in EQ2. Its probably a min-game in itself. Players hire themselves out as interior decorators and go to town with decorating. If I ever play another online mmo again, this is one feature I'll *need* to have to stay interested longterm.
I was actually going to enter your screenshot contest with some of my EQ2 pictures but they're on another hard drive and I'm not quite sure where it is atm :).
One caveat though about EQ2 since I haven't played in a few years. And SOE had a bunch of layoffs recently and EQ2 was hit hard on the dev team. EQ1 is still going strong and they want to keep EQ2 going too but with EQ3 around the corner in a year or so, not sure how many games they can run.
The below links/threads are pretty image heavy fyi...
EQ2 homeshow archives EQ2 homeshow current Hogs Head for you Potter fans Darkmoogle's house