Zynga's strategy is probably not sustainable. Hear me out:<p>The company that made the original game normally has enough time on the market to accumulate most of the users that are worth accumulating via open-market advertisements. It is likely that they hit "market saturation" prior to Zynga being able to clone the game.<p>Zynga has a massive existing userbase. When they clone an existing title, they're able to cheaply migrate some portion of their existing users over to the new title through cross-promotion. This is an effective way to retain users, but there is a significant problem: The original company (probably) already hit market saturation. The result, for Zynga, is that they can't really use this cloned game to grow their existing userbase. They can only use it to retain some users.<p>Fortunately for the original company, they aren't hurt all that much by Zynga's strategy - as long as they had enough time on the market before their game was cloned, the net effect of Zynga cloning their game isn't all that negative. The users that play Zynga's version tend to already have been Zynga users, and would only ever have played the Zynga game.<p>Unfortunately for Zynga, if this is their company vision, they will never grow their userbase. They will only ever struggle to keep hold of their existing users. They need to take risks and build unique, interesting games or they will face a slow death.