Gaming is the new social platform for many people all over the world. This excites me even more when I see entire communities being built around certain games! This is bigger than you think, trust me on this.
Some popular games that are pretty popular at the moment are:
League of Legends
World of Warcraft
WarCraft 3: The Frozen Throne
Call of Duty: Modern Warfare
FarmVille (FaceBook Game)
Restaurant City (FaceBook Game)
The Elder Scrolls V: Skyrim
There are many more games that I have not listed here that are popular and most likely will remain popular throughout the years.
What I can say is this: games are addicting. And gamers are people, so people naturally want to find other people to be around. This generation has found comfort in the virtual world and are spending more and more time online. I see this as a good thing, as I find that it is a great way to meet people and make new friends.
And to the more business-minded, it is increasingly worth your while to market to these avid gamers. ;-)