April NPD or Everyone Drinks except Nintendo

[Angrist]

Now the interesting question is:

Don't 3rd party games sell on Nintendo consoles because there are too many great 1st party games?
Or don't they sell because Nintendo fans are way too loyal/stupid?

I used to think it was the first. I couldn't even buy all the great Nintendo games, so why would I get the 3rd party games?
But now I'm starting to think it's the second... Okami and Boom Blox are better games than many Nintendo has made, but I doubt they'll sell much.