1hr at about DVD Quality will fit on about 1 Gig SD/CF?
Is the C3K and C760 using the same processor?
Is it really fast enough to decode Divix?
What are the current caveats?
About playing movies on the Z...
I play fansubbed anime and I'm happy with it (because sound isn't that important, I need it for sound effects and understand who's saying what in the subtitles).
I never tried to watch an entire movie in my mother language to check out quality in audio (of course you can change encode quality to improve audio, but I don't know how much bitrate the Z can handle).
Back to pratical matters: I "translate" normal divx to divx playable on the Z with the following:
mencoder "$1" -srate 24000 -vf scale=320:-3 -oac mp3lame -lameopts preset=15:mode=3 -ovc lavc -lavcopts vcodec=mpeg4:vbitrate=150 -ofps 15 -sws 2 -o "$2";
where $1 is the input file and $2 the output file.
You can check out the various options in the mplayer man page so you can see how much degraded the divx is going to be (and if still satisfies your needs).
As you can see the movie is resized to 320x200 (well, maybe less, maybe more to preserve aspect ratio in this case).
As far as I know, trying to watch a 640x480 divx on the Z isn't possibile (soooooo sloooooooow).
So in the end:
can the Z with pdaxrom play divx? Yes.
there are caveats? sure, see above.
And about the processor in C3K and C760/C860, I dunno... you have to check some review of the C3K, sure you'll discover something.
Ciao!
Andrea