This is our 1st trip during the holidays as well.... 11/12-11/22
From what I've read during all my "research"
Mickeys Christmas Party (Magic Kingdom) - must purchase seperate event tickets. Different fireworks, parade (from what I've read the parades are scented like the holidays... think gingerbread!), extra riding time on select rides, etc. From what I've also read alot of the parade/shows are worked into the regular planned days closer to Christmas but not sure if this is true. Tickets/dates available now.
Candlelight Processional (Epcot) - can pre-book ADR's for the dinner/processional packages but I don't believe you HAVE to book. From what I understand here it is a busy event and does fill up so ADR's are recommended. Dates/celebrity guest speakers release in July from what I've read.
Osborne Lights (Hollywood Studios) - Spectacular light show set to holiday musis that apparently goes off every 10 minutes or so on particular nights, includes snow on non rainy weather nights. Very crowded at the beginning of the night when they turn the lights on but I have read that it is not as bad if you wait till later in the evening. Lights go out 1 hour AFTER the park closes so you could linger towards closing and still be able to catch the "show."
Hotel hopping to see all the resorts decorated for the holidays. I think it's the Grand Floridian that has the "life-size" gingerbread house, just seeing the "world" decorated with holiday decorations I think would be magical.
If you look around on the DIS, AllEars.net, and Disney's own website as well as google specific questions you may have in regards to the holiday season in WDW you should find alot of the dates and events your looking for. Some of the information just hasn't been released yet too but you can look at years past examples to get a sense.
Have fun! I can't wait
