Once you get to DSLR, you’re not your average Joe photographer anymore, so I think DSLR is a pretty niche market. Also, since they discontinue old model when new model comes out, you don’t have them fighting each other on price.
I don’t think TV, car, DSLR, etc. will every drop in price like you see in HDD, memories, etc. New generation of these products will give you better spec, but price will generally stay the same or go up a little bit.