Sophisticated idea, no.

Sophisticated execution, absolutely. Zynga are extremely smart and dedicated about honing every single aspect of their games to enhance their addictiveness and virality. They didn't beat everyone else who wants their spot by being lucky.

On the other hand, it's a perfect example of how much it matters which parts of your idea are sophisticated and compelling. Here's an interesting take on why Farmville is so successful: http://flyv.typepad.com/warcraft/2009/12/farmville-considere...

As a hardcore gamer, you could call it an unsophisticated game. But I think as a product it's very sophisticated about what will encourage casual gamers to spread the word and come back regularly.