I don't get it.

OUYA says they'll pay out to devs at the usual rate - 70%.

If you do the math, you'll see that once you buy < $85 worth of content, OUYA will have paid out more than the $60 you gave them to developers. That's a really easy number to hit (especially since the promotion includes all one-time purchases). You could easily buy $500 worth of stuff and they'd lose like $300 bucks per person signed up. This promotion is good for consumers and developers, but it seems really, really dumb for OUYA themselves.