The mainstream market doesn't give a **** if it's open. It's irrelevant to the vast majority of users.
It matters to developers because it gives them more freedom to do what they want. Unlike Sony, Microsoft, or Nintendo anyone can make anything they want on the Android platform... there could AO rated sex games, for example. Something like Custer's Revenge or Blinding of Isaac would never be censored on Ouya.
The only condition Ouya seems to stipulate is that the games be freely playable in some manner, but considering the hardware itself is open and easy to hack, even this limitation can be bypassed and it won't void the warranty.
Being open doesn't make something good.
It doesn't make it bad, either. And the Android platform is already mainstream. Ouya won't be niche because Android itself isn't niche, and Ouya is Android.
Openness is usually a bad thing for the mainstream User.
Would you care to explain?
Which is a big reason beyond the nerd hitching I think windows 8 is going to succeed.
Windows 8 and Windows 9 and all other Windows is going to succeed because of the Windows monopoly. Microsoft has 90% of the desktop market and there's no way that is going to change anytime soon. It can be slowly eroded over time, but windows isn't going away in the near future.
Windows 3.1 and Windows 95 succeeded because they were easy to use (relative to most offerings of the time) and because it ran on IBM compatible PCs and was just the best option for the time. Since then Linux and other operating systems have developed which have closed the gap on ease of use, but the market has already been locked up in a monopoly and its tough to break that. Apple made a good move by switching to IBM architecture, because now its possible for Windows and MAC to dual boot on the same machine, so this helps, but its not going to instantly result in Windows being defeated. Over time, maybe, but we aren't there quite yet.