What I wonder is whether the newer hubs are put together to the same quality standards as the older ones. Sizes of pinions aside, we know that an AW 3 speed hub is MUCH better sealed than any modern hub (Rohloff possibly excepted). To prove this, try filling your new Nexus or other hub with oil. If the old hubs keep oil in that much better, they keep crap out that much better.

If we expect modern multispeed hubs to continue chugging along for 50+ years of ridiculous mileages, the way the AW does, then we're probably kidding ourselves. If, however, we compare them with the wear cycles and associated costs of running an 8+ speed derailleur in all weathers, they probably still win, and certainly win on convenience (I know which I'd rather clean after a wet run on salty roads)