It's amazing that technology and virtual space itself has advanced to the point where now whole worlds can be created, and therefore whole lives could be lead in what is just a reality made up of "1"s and "0"s. It's actually really baffling to me. As a long time online video gamer I've had ample experience with virtual worlds of many different kinds, so I guess my viewpoint is kind of biased when I say that I love them.
Virtual worlds can be used for a variety of things such as creating stuff online such as with second life where people lead whole careers by creating different things for the game such as theme parks or costumes since real people will shell out real money just to obtain a virtual creation. Virtual Worlds can be just about having fun, as well with MMORPGs (Massively Multiplayer Online Role-Playing Games). In these types of games you team up with friends or even perfect strangers to defeat difficult monsters and earn rewards like armor or prestige among people on the server. It's all about achievements and conquering in games like those.
Virtual worlds have also helped to foster a ton of new creative outlets. A good example of this is the company known as "Machinima". They provide people with the tools and legal support needed to use copywritten game character models and soundtracks to make their own videos with on YouTube. Many people have created comedy short clips using World of Warcraft characters or even used it to facilitate stronger story telling and created movies of their own stories with tools and support like this. And they also make money with it, too!
What I would say a virtual world does best, however, is facilitating communication. I can hold a conversation with three different people, from three different parts of the world, with three different accents, simultaneously in just one space. Sometimes you don't even have to speak the same language as games like Final Fantasy 11 and 14 have integrated translate features into their games to facilitate team play between Japanese and English audiences. (You're really restricted to just the bare minimum of words and phrases, but even that alone makes up a several hundred word library. It's kind of amazing.)
However because the virtual world is so amazing many people end up shirking their responsibilities in real life in favor of the virtual one. There are countless stories and running jokes of "losers" with carpal tunnel who do nothing but get fat playing games online and making their characters more "epic". I even knew a guy who quit his job in real life so that he could work harder at making events and getting to know more people online. That was probably the most extreme example that I've ever personally come across, especially considering he wasn't looking to make money off of what he was doing (Which he could if he wanted to). It was baffling.
The future of the virtual world is only going to blur the line between itself and reality further, in my opinion. With the implementation of virtual reality glasses and graphics only coming closer and closer to emulating what the real world is like, maybe one day the term 'virtual world' will have a much more concrete existence than it does now.
Works Cited
At Hearing, Real and Virtual Worlds Collide: Forget C-SPAN: Congress Goes Interactive. Washington Post, Wednesday, April 2, 2008; Page D03. available from: http://www.washingtonpost.com/wp-dyn/content/story/2008/04/01/ST2008040103032.html
"I've Been in That Club, Just Not in Real Life" by Dave Itzkoff, The New York Times, January 6, 2008, available athttp://www.nytimes.com/2008/01/06/arts/television/06itzk.html*