I won't be going to Disneyland for the 50th because my AP is blocked out. ANd to be honest, I wouldn't go anyway. I stop in at the park maybe twice a month (when there are no block out dates) and the thought of the tens of thousands of people at the park, in the hot weather, sounds like a nightmare to me.
I can understand wanting to be there for the "historic" reason, but is it really worth the hassle? I am the same way about the Rose Parade on New Years Day. As a life long Californian, I feel I should do it at least once. But it doesn't seem worth it to me to spend a freezing night on a sidewalk, when if I want to see the parade I can see it all day on TV (and with a hang over).
I do remember in high school going to the all night party for the 35th birthday. I was cool back then because the park opened at midnight and was a special ticket event, with the general public not being let in until 8 that morning. It was fun to hit the park in the middle of the night (like grad night) in a park that was not crowded. But by the mid afternoon, after being up all night was running our batteries low. We left by 4 because it was so crowded and after being up all night.
For those going to this event, good luck. Better drink lots of coffee. I think you may be in for a grumpy day.