I agree with DisMike, first off, he was there last year, so that is about as good as an indicator as you can hope for. Second, that day, and the 2 days after, until Sunday, are blocked out for So-Cal pass holders. And locals make up 70% of the visitors to DLR.
Now, I am sure since that is a holiday weekend, there will be more out of town tourists, but I wouldn't think more than 70% more. So I also expect busy, but not packed. At least that is what I am hoping for!!
Now Sunday, when the blockout is lifted and it is the first day locals with passes can come visit the holiday decorations? I expect that day to be crazy.
I plan on spending all day in CA.