I feel like the OUYA is a bit out of luck considering how fast the mobile landscape is moving. Tegra 3 is being surpassed (at least technically) before the OUYA launches, assuming the OUYA even hits its "early 2013" release.

As mentioned on here and elsewhere, maybe development will cater to the lowest-common-denominator as far as SoCs go and the OUYA will be OK, but I feel like the audience for the OUYA won't particularly like being on a last-gen mobile SoC.

I think OUYA would be smart to re-target it at sub-14 year old kids, and not really at the more hardcore gamers. At least until they release a version with the latest and most powerful ARM SoC.

Kinda, but isn't it a pain for developers to have to account for all these kinds of Android devices?

I don't have any experience developing for Android, but I can imagine developing for Android phone handhelds is hard enough already.