I'll start with my opinion. We went to
MVMCP on Nov.30, 2004. We had been at MK the day before the party, and spent party day at Epcot and headed over to MK about 4:00. We stayed until the party was over. during the party we saw the Mickey's Twas the Night Before Christmas, the parade, Belle's Storytime and Wishes. For the Twas the Night Before Chritsmas show we had to get a seat over and hour before and we were still 2 rows fro the back, and DD7 had to sit on DH's lap

.
We are going to Disney the same time this year Nov.29- Dec.6 and we WILL NOT be doing the MVMCP

For us it was not worth the cost or the time. We did so much more the day before at MK than we did during the party. The party was PACKED with people. The day before, we walked on to almost every ride. During the party we waited at least 15 minutes for everything, and 30-45 minutes for rides on Fantasyland. The shows were nothing to rave about. The first parade was impossible to see so we waited for the second one. Even then we had to line up an hour ahead, and then got crammed over at the last minute by the stupid people who decided to show up late.
By the end of the night I was fed up. I was expecting lower crowds and shorter lines because everyone on here said it was great. Maybe years before it was that way, but not anymore.
So my opinion is save your money and just go to the parks. Spend that money on a nice dinner when the party is going on. You will be glad you did!
Sorry to sound like such a stick in the mud, but that was my opinion. I'm sure you will get a bunch of people saying it was great too. Either way, have a great trip!