> Things are further complicated by mtd changes not being 
> tested against yaffs. 
> As a result, changes in mtd can break yaffs.

There is a ray of hope on the horizon on this front.  Various MTD
developers monitor the yaffs list these days, for example.

Meanwhile, starting last week, I have a regression running at PalmSource
that verifies that recent MTD changes don't break YAFFS2 compatibility
in a detectable way.  Look to two things as we go forward:

1) I will run this daily against updated MTD from their CVS tree
2) The regression will become more robust over time.

Eventually, I hope to release this as part of a YAFFS2 testsuite from
PalmSource.

Marty