From the review:
The buttons made me angriest, though. Instead of labeling them A, B, X, and Y, like every other manufacturer ever, Ouya went with O, U, Y, and A. The A button is where B should be, and O is where A typically is — so every time the Ouya said "press A to go back" I pressed O and went forward.
Sigh, another casualty of Xbox brainwashing, much like the idiot who criticized the Wii U for supposedly rearranging A, B, X, Y. In the non-Microsoft universe, the A is right where it belongs, but the Y is where X should be, and the O is where ⨉ should be.
I think the real problem is this: if you're going to use O/A for forward/back, why assign the left button to "forward"?!? (I suppose I'm being left-to-right centric, but the few screenshots I can find of Hebrew web browsers don't seem to mess with the basic idea that left is for back.)