Now, I don't have a P800 (not yet ) but I would really like to know if the photoshop macro proposed at the bottom of the page will give good results on the P800. I have tested it myself with an IPAQ and also on my computer, converting 16 MColor JPGs to 4096 colors and it is VERY difficult to notice the difference.
Anyone with a P800 and photoshop cares to try? Here is the link to the macro: