I think some people participated; I gave away some delibird and vulpix with stones, and I got back a delibird with a sunstone and a charmander nicknamed 'Merry Xmas'. Maybe fewer people had time to breed and collect enough to participate?

I only ran into one Merry X-maser and I got a Zorua with the Destiny Knot on it(whether it has good IVs or not who knows, it was unmarked), so other than that I ran into the standard Wonder Trade fare with Froakies, Bidoofs, Riolu, Ralts, with a few gems here and there.