Now, I'd say you knew mobile phones became some sort of commodity when you started seeing kids with them. And I don't mean teenagers, I mean 10-year-olds or younger.
Well, now it's big digital photo cameras. I was touring around Portobello Road market on Saturday and saw an astonishing number of little boys and girls brandishing either DSLRs, which were bigger than their heads or, at least bridge cameras (still with big bodies and heavy lenses). So, I dare say that DSLRs and their cheaper bridge relatives have became commodities. And it's probably a good thing.