World of Warcraft is the most successful mmorpg ever made, nothing has matched up to its simplicity to get started and play. Although some people cannot afford the WoW subscription fees of $15 a month and are suprised by its continuous success. For a game that cost $25 and is continuing to have expansions that cost more than the game itself.
Last month I was extremely bored and thought maybe i should try WoW cause i've heard great things about it, 10 minutes later i couldn't put my laptop down. When the trial ran dry i had to buy the full game and i have been saving for weeks to get the Battlechest to save 15 bucks to get the burning crusade with it. Although Blizzard has though about making the game F2P i think they should go with that decision and increase their fan base by this means.