I love that this game is catching on with an older crowd! I am 23 and have no shame in saying I greatly enjoy this game. It's got a great deal of gameplay depth, and there are lots of little dirty jokes snuck in there as well. It's a definitely sleeper hit, and I think it will well exceed initial expectations.
The estimated 353k sales is way under what it will probably end up at, its focused on the whole family, and there is even a kids tv show, which kids watch, and so you will have millions of kids wanting to play this..
I think Viva Pinata is more of a strategy game than a simulation since it's nothing like real life gardening. It's a strategy based game because you have to plan out how to improve your garden to attract Pinatas, and then taking into account the Pinatas you attract will affect what other Pinatas you can attract.
A lot of times strategy and simulation also overlap, like Sim City, Tropico (simulate dictatorship?), Railroad Tycoon, etc. When I think pure simulator game, I think something like Flight Simulator.
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