All you proponents of Polyurethane (Gorilla, etc) might be interested in the Fine Woodworking test appearing in the August 2007 No. 192 issue.
Compared to Type 1 (waterproof) PVA glue, Polyurethane only produces 58% the strength of the Type 1 glue. It proved weaker than even liquid hide and hot hide glues, according to tests done at the Department of Materials Science and Engineering Case Western Reserve University in Cleveland, Ohio.
Their test also show that slow set epoxy not to be any better than the Type 1 PVA glue. The tests were done on Maple, Oak, and IPE with various types of joint fits.
Ed...