After wondering why we do not see more companies with multiple MMOs linking their games, I have come to wonder the same thing about Facebook. The leading developers (and many of the next tier) have about a dozen games each, usually clones of each others’ (“No really, our farm is different!). Despite using Facebook as a common platform, the games are almost entirely separate. They frequently even have separate cash shop currencies for their games.
There are exceptions. Cross-advertising is more common, by which I mean not just having “play our other games!” at the top, but placing decorative items in each game that reference the others. PlayFish (EA) has one currency across its games. Digital Chocolate sells you in-game character cards that apply to all their games, so your new hero does whatever is appropriate in all of their games at once; that seems like a great incentive to try more of their games and to spend money on them.
Why not have incentives to try all the games, really get someone entangled? The same company will have a farm and a restaurant and a city and a pet shop and… Why is there no option to send crops from my farm to my restaurant? Why can’t I have my restaurant and pet shop in my city? Why can’t the safari game send pets to the pet shop? If you could link all these games together, you would more or less have an MMO, one that is more crafting- than combat-focused.
Then we just need a way to link Farmville to World of Warcraft, and the world will end.