Well supported fun game with surprising depth and a great community focus
World of Tanks has all the signs of becoming a huge game, a proper "Freemium" offering where you can genuinely pay no money and get 95% of the experience of the game. Yes you can pay money into the game and it will get you to higher levels quicker or buy you slightly better ammunition and consumables, although helpful they certainly don't imbalance the game. Even the "premium" cash only tanks don't imbalance the game, and rarely do you see more than 2 or 3 in any one battle (not bad out of 30 tanks).
The back end of the game is also simply designed and easy to understand but once again carries a huge amount of depth, all this backed up by some of the best out of game support and community sites. Speaking of community - Wargaming.net go out of their way to establish community feedback and do lots of competitions that sit outside of the game, with artwork, paper tanks and costume competitions for fans and players mixed in with regular news, updates and in game activities.
Regular free updates, loads of new maps and even more new tanks from countries around the world mean the game doesn't get stale even for experienced players, all the while managing to avoid the Games Workshop approach of making the new stuff better so everyone buys it.
Like a schizophrenic gymnast, this game is all about the balance, timing and depth.