Just wanted to mention that MNSSHP in WDW is not the exact same as the Halloween Event in DL. I think in DL it's just called Mickey's Halloween Party.
This page seems to have some good info about all the Halloween decor/events at Disneyland: http://www.wdwinfo.com/Disneyland/Events/Halloween.htm#party
Ooh, thanks for the link. If this year is anything like last year, the dates we are going have an advance ticket purchase that is $10 less than the day of, so tickets would only be $49 per person, except the 2 year old. We may have to plan to do BBB, Ariel's Grotto and the Halloween Party on the same day, so the girls will be princessed up.