Btw. I have allready written a nicely working chumby emulator using MozEmbeded (on the Desktop). I'll happily share all the code (python).

It basically works like this:
1) wget CHUMBY_CHANNEL_URL (somebody allready posted something like this in this thread).
2) parse the channel XML file
3) show first widget as specified in the channel XML file
4) show second widget, ... show last widget, check if XML was changed
if yes goto 1, else goto 3