It's neat, but only a sister group at best. Keep in mind that at the same time orthozanclus was around, so was Scenella, the monoplacophoran. So, the shelled molluscan lineage was already in place, and shelled guys were where cephs come from too.
When you look at kimberella, the precambrian mollusc/mollusk (British vs. American sp.) you can see it's not far from being exactly like a polyplacophore or monoplacophore. It's just not shelled yet. Attached is a nice pic of a kimberella. It's about twice the size of the original. The original is around an inch long from mouth to end. Actually the thumbnail version's about right, maybe a little small. You can see all the little gills around the edge, and a deeper spot where the thick noncalcified mantle was, with a poo trace to the right and a head end to the left. Enough traces of radula like feeding from the time makes me think it's can easily fit into mollusca.
All that aside, the orthozanclus does unite a couple oddball cambrian 'explosion' beasties into something one could clearly speculate on. The tree of life is getting nearer to complete, albeit perhaps asymptotically.