This shouldn't be compared to PCs, or consoles for that matter. It's not going to compete with PCs because it doesn't have the power, nor the same style of games (i.e. it's mainly controller based). It's not going to compete with consoles, because it simply doesn't have the power, nor the backing behind it.
Let's be honest here: this is an Android device, this is a mobile device without a battery. It's got a Tegra 3, which is a pretty ballsy bit of silicon for mobile devices, I've definitely seen near-console level graphics and gameplay using that, and other high end chips.
However, I really don't see this product doing very well. By the time it comes out, we'll probably be looking at Tegra 4s etc., so this will no longer be high end hardware. Mobile tech just moves too goddamn fast, it's very tough to plan things ahead, especially without major backing from supply companies.
Then it comes down to the fact that what's the market here? Most likely, it's a fairly niche (albeit large) group of hackers, android fans, maybe some retro gamers, etc. As someone who's a huge android fan, I've already got a couple android devices, and both of them are at least as powerful as this console is. They both have full bluetooth and USB capabilities, as well as HDMI out. So what's the draw with the Ouya?
Frankly, I think the proliferation of smartphones is going to kill this device's mainstream appeal. Why buy something new, when you can use what you already have. I think for it to do well, it should implement Google TV, including the HDMI pass through and IR blaster. I'm not sure how much that would affect cost, but I know I'd buy it if it supported that. Also some NFC would be nice, if only for bragging rights.
It remains to be seen what will happen from the hacker scene on this. I think that will make or break it, if hackers can get it doing some cool things, I'm in. Hell, I might still be in right now, out of pure nerdy curiosity. But do I think it'll amount to much? I really don't know.