http://www.motorauthority.com/news/1106388_ram-just-unveiled-the-hellcat-powered-ram-rebel-trx-concept?fbfanpage#image=100567713 Man that thing sounds badass!!! :C:B Texas State Fair link
There are three Hellcats (2 Challengers and a Charger) that I see at the airport parking garage every week. I've heard one of them running, and man that exhaust note is sweet.
I'm not interested in one in a 1500, but if it really makes its way into a Grand Cherokee, and has similar towing specs as the current SRT, it will be very tempting.