I don't think there's any way the i760 is going to be released before Thanksgiving. The Voyager was just announced for mid November release. Given that the i760 hasn't been announced yet, I can only assume it won't be released until sometime after that. Given that it'll be too late for the Christmas season anyway, I expect mid Q1 next year.

I doubt the accidently shipped i760's have the final firmware. It's going to be interesting to see if Verizon will provide a way to download and install the final release. The more likely scenerio will be that you'll be required to return the phone and pay a fee to get it flashed to the final firmware release.