I think not just 36XX take a look at OmniaHD as an example.
http://reviews.cnet.com/smartphones/...-33527298.html

http://www.gsmarena.com/samsung_i8910_omnia_hd-2691.php

It recording at 720p and play back because of AMOLED
This really show that N900 is somewhat capable of handling 720p if and only if the OS allowing it and having the right optimised codec.
I wandering why Nokia didn't take some risk in enabling it. Recording at 720 would be possible too, I believe I read somewhere about this that N900 can do 720 but will be on the edge and may be difficult to do it with its current OS.

But on the other hand Nokia can't even get the 848x480p to work properly already. I don't see they can get anything done with this at all. Even samsung can do it with almost identicle hardware lol this is terribly embarassing for me personally.