I enjoy playing with HTML, but I couldn't begin to put together a website that handled any kind of commerce and needed a secure purchasing arrangement. Also as MMario mentioned, the sophistication level can involve many things (updates, databases, input, cookies to individualize visits, animations or other pizazz.) I think where a lot of commercial sites fall short is that they don't use good graphic design. This is where the artsy folks really know best. Then my pet peeve is that lots of technically complex sites with beautiful artwork will have glaring typos. It really takes a team for a sophisticated commercial site.