Reading them over, it's sort of depressing to see how inadequate any of them is at really communicating the problem and prescribing a solution that's both correct and generalizable.
The reason I'm back to the topic is that recently we've begun work on a web-based map of Second Life . The intent of this is to solve the following problem. It's almost impossible to understand Second Life until you actually enter the virtual world -- a paradox that makes marketing it and creating a message that can be replicated and buzzed about, very challenging.
One of the difficulties arises from the fact that when visitors to our site see pictures and screenshots, they don't understand three basic facts:
1. All the people in the pictures are operated by real people
2. Everything that surrounds those people (ie) the whole world, was built by those people, not by some video game company, and
3. The virtual world is VERY big and is growing VERY fast in real-time.
So the map on our homepage is an attempt to show new users a view of SecondLife that explains at least #3.