Somebody let me know when Snopes is cited in litigation... LOL
Peg O'Brien, Public Affairs Associate of the NFPA, “follow the manufacturer’s instructions, most of which say you should leave your cell phone in the car while refueling.”
The official position of the NFPA is to punt the liability to the cell phone user and the manufacturer responds in kind again sending the liability on to the user of the phone.
Cell phones contain lithium batteries which have been known to explode, catch fire, melt and overheat.
If that conversation is that important to you while you are pumping gasoline then you assume the risk just like every other "at risk" activity that you engage in.