Tedhl, I see the triangles you mention. So it does look like rows 19-21 are over the wing and in compartment two. The 346 is much longer than the 343. There is a good picture of a VS one as an example:

http://www.airbus.com/MultimediaElements/1034.jpg

Notice the saying on the aft end of the plane.

I have a feeling that CX might change a/c types between now and flight time, so I guess I will stick to rows 11/12 in the meantime just in case.