Toyota is updating the RAV4 this fall and adding a hybrid with a rated towing capacity. It will be a similar drivetrain as the Prius in the front plus electric drive in the back for traction control. I've seen mixed estimates as to actual towing capacity ranging from 1500 to 3600 lbs.
One advantage with a hybrid and camping is you could use the car as a generator. I would suggest a high amperage separate battery (or two in parallel) as a buffer to prevent the onboard 12v battery from depleting if the car gets shut off and if the car is off separate the circuits. I have a Prius V myself (which I will not tow with) and I want to set up a battery to go with it to use with my 1000/2000 watt pure sine invertor in case of power failures. (keep the beer cold and maybe run a window AC unit) I have run a window AC unit for about an hour on just a five year old deep cycle battery just to see if it would work. The Prius V 12V system battery is not a starting battery and does not put out a lot of amps. It is there just to run stuff like the car computer, lights, etc. You cannot jump start someone else with it. If you leave the lights on and kill the 12V battery, it can be jump started with another car..but jump starting it just involves supplying an external 12v source (like from a second car which should be turned off) and pushing the "on" button. This turns on the cars electrical system which turns on the DC to DC converter which then supplies 12v from the high voltage (288v?) traction battery. The DC to DC converter has a 100 amp fuse protecting it on the output side. So, whatever method I use to charge an external battery from the internal battery, I need to be sure I don't draw more than 100 amps (minus any other accessories in the car) I heard that fuse is expensive. As a generator, the gas engine will turn on and off as needed to keep the high voltage battery charged.
I have read online where someone used a similar setup to run his house after a bad storm and it used about half a tank of gas over five days. (it was online so its gotta be true)
For now, I'll stick with my wife's Honda Odyssey as the TV and drive my Prius V as my daily ride. That is unless my wife wants to downsize to a RAV4. The RAV4 is about the same size as the Prius V. It just sits higher, has a tow rating, and probably gets 25% less in MPGs. (it is not rated yet)