We went in 2008 and 2009 with very different experiences. I believe in 2008 we went on a sold out night, the 2nd party to the last or possibly the last one - I don't recall. Last year, went the same week and was on the last Wed or Thursday party of the season. Not sure if it was sold out but I think it was.
2008 was absolutely great! Even for being sold out, we had a blast and crowds were managable and honestly, it was the highlight of our trip, truly. I won't say crowds were non-existant but it felt like it was a limited ticket event and we got to do so many things.
2009 to me, was a nightmare. Wall to wall people, not being able to move and I felt rudeness from other guests and I really think it was because of the packed walkways etc. The line for cookies and cocoa in tommorland was outrageous. In '08, we did go to Adventureland for the cocoa and it was empty but I don't know how it was last year since we didn't go to that spot for the cocoa.
I was so irritated from the high crowds and it was super warm with all of the people packed in that I actually swore off Disney period lol. From my ticker, you can see that I didn't really mean that but DH said he will never again pay extra to put up with that. DS wanted to go again this year, DH said that I could go with DS but he wasn't coming. I decided none of us will go, it's just not worth the money for the over crowded experience.
Having said that, I am glad that we went, at least in 2008 because I really love that parade and fireworks. 2009 didn't feel to me at all that it was a limited ticket event. (I will say that after returning and I posted my view of how crowded it was, there were others who responded who didn't share my view and thought it wasn't so bad sooooo who knows!)
We decided we will be going to Sea World to see their holiday decorations and shows this year instead. Actually, I am really looking forward to seeing their ice skate show, water and fireworks show!