I'm in the same boat, OP. I'm switching from an iPhone 5 and trying to decide what's best. I've had a galaxy s phone and a galaxy nexus before but I always come back to apple. Now I'm looking at the nexus and the turbo as the new iPhones don't appeal to me that much.
I love the concept of a nexus, the vanilla android is sweet. However, the Moto overlay seems very clean and I LOVE all the hand gestures and voice commands, not to mention the battery.
Size wise the nexus does make me nervous since it's such a big jump from an iPhone and spec wise the turbo and nexus seem pretty spot on each other (for the most part). I think for me, the battery is having me lean towards the turbo right now.
Finally, while I am not someone who "tinkers" with their phone, not having the option is kind of a bummer especially since I've been in iOS prison for so long.
Hopefully I have the patience to wait for reviews to come out on both devices and hold them In person but if not I'll be getting the 64gb turbo tomorrow.
Final thought, maybe you should make a poll for which device and why and see what you come up with. I'd also suggest putting this thread on the nexus side as well just to keep all biased (or the illusions) out.
Edit: sorry for all the grammatical errors, I'm typing on my iPhone