It makes perfect sense. In the same way that FishVille targeted rival company CrowdStar's popular Happy Aquarium game concept, PetVille would neatly knock on the door of rival Playfish's successful title Pet Society.
Zynga is perhaps best known for its wildly popular game FarmVille, but is clearly not content to rest on its laurels and is aggressively building out social games with similar casual mechanics and a reportedly impressive revenue stream from in-game currency sales. Just how big is the social games space? Big enough to prompt industry-leading video game publisher Electronic Arts to snap up Playfish for as much as $400 million.
With shorter development cycles and growing revenue streams, it's no wonder the traditional video games industry is taking notice, as sales data from consoles and software continue to plummet. For many of the same reasons, the industry should be worried about Apple's iPhone too.