Ya my friend has a nexus 7 and we have developed for it already. But that cost him €200 I think. OUYA is €100 cheaper than that.Being a student still that 100 can mean a lot.
Yea, that's a crappy position to be in. Personally I'd recommend penny pinching and trying to save up for the nexus though. It's more expensive, but it's also a lot more useful. With a bluetooth keyboard and a stylus you could replace most of your school related things (notebooks, laptop, some text books, etc) on top of having a development tablet with the same specs and platform as the Ouya.
Thats actually a good point. I would be getting the development possibilities plus all the other functions that come with the nexus while the ouya only gives me the gaming side. The little I have used of the nexus I have really liked.