Just returned(I literally just sat down from unpacking) from my quick Sat-Sun trip. Saturday we went and hit all of the outlet malls, and sidewalk sales for Memorial Day, and THEN went into the City around 3-4 pm. It was perfect, we had a great parking spot, stayed until closing, and there was hardly anyone in the park by that time of the day. All my photos would show this seeing that they were all void of people! Overall Great day!
Today was another story. We were there at opening, and it was not too bad. Throughout the day, around 11-12 it started getting a bit more and more crowded, lines were getting longer and longer, and then as we were leaving a HUGE influx of cars were lining the road from the entrance all the way to SOTH. I imagine that after 3 today it'll be pretty bad with the next day free offer.
I would never turn down a trip to the City, but tomorrow might be a bit crowded early in the day, and after 2-3 would be the time to go if you can seeing that the majority of the visitors will be heading back home by that time.