We, at ASIT VD (www.asitvd.ch),
are currently working on making more data available on Vaud. We
would be
happy to get input from the OSM-ch community. I sent a message
some months
ago on this list [1] for this prupose... but no answer so far
;-)
About your original email, of course ortho-imagery would first come
to mind. Although not likely, but maybe in your position you heard
of imagery at the communal level?
Also on the canton level, cadastral data could be of help to compete
with our french neighbors in polygon count (some will appreciate ;-)
).
Speaking about buildings, there is the 'recensement architectural du
canton de vaud' that could be of help if not full cadastre. We could
also switch to french.
Yves