But traditional gamers often spend more money than casual gamers over a longer period of time. Casual gamers are more inclined towards single experiences (Wii Fit) whereas traditional gamers often prefer to try many, many games, often at launch price.

Zynga begs to differ. "Traditional gamers" are here to stay. The same can't be said for casual gamers.

The categories themselves are pretty polarizing. I consider myself "casual" when it comes to the time investment and active engagement required for MMOs and certain big budget titles, but "traditional" to "hardcore" when it comes to the indie games I buy off Steam.