I am waiting for prices to drop too - we got an unbelievable deal back in May with Budget for $5 a day for a one-way - we flew down, picked up the car and drove it all week, then drove home - it was a compact, but what a savings even with gas ($83 for week with tax plus $167 for gas). We did a one way because we had a stop on the way home for a side trip.
This trip (Oct. 20-Nov.5) I will be driving down and home because I have to pack the car for a side-trip camping at Talladega before two weeks at WDW. So far, because it's 16 days, the cost is around $700 from Buffalo airport. Having paid $110 a week last Christmas at Alamo for a full-size, I refuse to pay $300 a week for the same vehicle that I already own. Our Impala is 3 years old and needs new tires, so if the prices don't come down to rent a car, I will just get the new tires and drive our own car down.
Still watching for deals though, so keep posting as our dates get closer!