Nook (e-ink) or Nexus 7 - which should I buy?

I've got a question for the Verge community. I just bought a Nook e-reader (the Nook Simple Touch with GlowLight - what a name!), and I'm planning on rooting it to use it for RSS, Instapaper/Read it Later, and other services like that. I am also considering returning the Nook and buying the Nexus 7 instead. With the Nexus, I'd be gaming, reading, listening to music, and watching movies, but with the Nook I'd only be reading. Keep in mind that I do have an Android phone, so my phone can do a lot of this, but not as well as the tablet (except for music). I'd carry the two in all the same places since they're nearly the same size. My main question is - which one should I buy considering that I have an Android phone? Also - price isn't an issue.

Also - for anybody with a Nexus 7 or other tablet - is reading on it bad for your eyes? I haven't read long enough on either platform to know what happens to me in terms of eye strain.

Thanks for your replies!