I "was a resident" (dont say played!) for a while last year. I hear it's soooo much bigger now. I still login to the SL webpage occassionally to see if anyone on my friends list is online at the moment and there are a LOT of people that have been residents for years.
I even (almost accidentally) made a couple of hundred REAL US dollars with some land that I purchased in a new expansion and sat on for a while trying to dream up something to do with it. Then I sold it and made a ton of Lindens.
The in-game tools and scripting was surprisingly powerful.
If you are curious, I'd highly recommend you check it out.