I find myself quite conflicted on this, too. On the one hand, I love the better battery capacity (which is critically important to me, because I'm home very rarely and sometimes can't plug my phone in for long stretches) and expandable storage. I work in a warehouse cooler and get extremely poor reception in there, PLUS my data plan is very tight. I could probably get by on the 920, but I really, REALLY want to see some real-world battery comparisons. Does the larger screen impact battery life dramatically? Did Nokia use more energy-efficient components? These are answers I need before I decide.
Also, I do wear a collared shirt on many days, so the thinner-and-lighter would be a bonus for me. Also, with the AMOLED vs PureMotion+ (or whatever it's called), I guess I'll have to see them both in motion before I decide.