Ok so there are 3 types of main photographing cameras as I see them.
Digital ones that are slim and carried usually in a pocket (these are the ones being replaced by phones) They can take great pictures and are generally high quality, they are pretty cheap too.
There are high end cameras, ranging anywhere from 300-1000$. These feature replaceable lenses, better flash and technology. I don't see smart phones ever replacing these, as they can be customized, attached to bi/tripods ect. I have a canon Powershot myself.
There are the disposable cameras too, used mostly as a cheap way to get photos. I've used some with pretty decent quality (and it can be touched up if you get it digitaly developed)
Main answer, pro cameras won't be replaced because smart phones can't possibly keep up (do you think a smart phone can replace a ps3, or PC/Mac?) but they will drive casual photographers away