This might not be popular, but; the Itouch and iphone 3gs is an excellent DAP - not perfect but as an audio device, they are excellent (and yes i'm a serious audiophile).
My DAP is the Sanza Fuze, but thats mainly foor its drag 'n' drop support of Flac, ichoons drives me crazy!
I have the N800, N810 and N95 - and the audio SQ is very poor on both the N800 and N810 - the N95 is better but no where near the itouch sq. I tried to use Flac with both the N800/810 and it was never quite up to the task. I'm hoping the audio from the N900 is better, and with some decent media support.
BT