I have been told the opposite. They have no choice (unless Disney wants to make the payment for you), they must increase the tax. I have been receiving updated faxed reservations daily with the following note on the bottom:
"Orange County recently adopted a tax increase effective September 1, 2006. Our rates have been adjusted for reservations with arrival dates of September 1, 2006 and thereafter due to this increase in local tax and other costs. Therefore you package price has been adjusted"
I have no idea why it says and other costs it appears just to be the tax. I have been getting these for a few days now and they seem to be at the beginning of November 06
Remember the increase is not on the whole package just the hotel portion