As far as I know, every archtop that I have ever heard of has been made of plywood ("laminate"), including Gibson L-5, ES-5, etc. (correct me if I'm wrong). Any flat top acoustic worth it's salt will usually have a solid piece of wood (cedar, spruce, maple, mahogany, etc.) on top, braced by flat pieces of wood underneath. An archtop, on the other hand, is formed by steaming the arch into the wood. Laminate will shape easily with steam and is stronger than solid wood - it is unlikely to split like solid wood. Hopefully, Epiphone uses high quality 3 or 5 ply laminate and not Home Depot G1S plywood or sheathing.