I travel extensively for business, and have not noticed any adverse reaction to my vaping inside of domestic airport terminals. I will stealth vape in the lavatory during the flight (usually about halfway through it) if I cant't wait until we land, but really layovers and arriving early enough to make sure I get through security without missing my flight are the worst times for me. It is tough to fly anywhere in the US today direct that is more than a 3-4 hour flight anyways, so it is usually not much of an issue.
I do not see these rules changing to accommodate vapers, and don't know that they should. Space is very tight on a commercial flight. I probably wouldn't vape in my seat even if I could.
Also of interest, I flew on Turkish Air over the summer, and they were totally ok with me vaping, as long as I went into the bathroom to do it. It was business class though, and a 12 hour flight.