I don't care about the thinness that much. The 808 is not that thick of a phone. I'm realizing now that I kind of wish my Lumia 900 were a bit smaller. Thinness is great, but a tall, wide 4.3"-4.7" phone is just uncomfortable to use one-handed and that is more important than the thickness.
If Nokia made a PureView in the same form factor as the 808, only with WP8, a faster processor and higher resolution screen (4" is fine, but not the 360x640 screen resolution is pathetic) Give it 1280x720 in a 4" screen and I'd buy it in a second (definitely doable since the iPhone has 960-by-640 in 3.5")
After carrying this wide/long brick around for a while, I really do not want another 4.3-4.7" phone. I'm HOPING that there will be such thing as a 4" premium WP8 phone and I don't have to have another huge phone just to get the best features.