Where are all the others gone? No more comments/interest?

It's a platform in some sense, in that people can create games (and lots of other things) there. But it's also more than just a platform, because people *have* created so many things there, and because so many people are there to interact with. You can hardly rent a beach house and go out dancing on a “platform”, after all.

(Blue Mars in its current form is more of a platform; it's sitting there waiting for people to create worlds on it, and for those worlds to draw people.)

I don't know of a better word for Second Life than “world”. Just like the real world, it has only the narratives that you (and others) create; none are built-in. And just like the real world, the people are very unevenly distributed. A random square mile of North America would be no more populated than a random parcel in Second Life. You have to put in the effort (and it's not much) to find things that interest you.

Glad you had your revelation. It's interesting how many people we've seen in the past couple of weeks saying “hey, this is really pretty neat once I stop expecting it to be WoW!”…