I was there and it was jammed, but really, it's always going to be jammed on a holiday, and I didn't find it to be all that much different from summer trips I've taken. I got up early, used FastPasses, and made my touring plans based on what I knew were less popular rides. For example, I got a FastPass for Buzz Lightyear in Tomorrowland, then saw the Carousel of Progress and The Timekeeper, and rode the Tomorrowland Transit Authority ("Paging Dr. Morrow. Dr. Tom Morrow. Your party from Saturn has arrived. Please give him a ring."!!!!) twice. By that time, it was time for Buzz. That took a couple of hours, then I got a snack, watched some of the band playing in Tomorrowland, and left for lunch.
Of course, it was a solo trip for me, and I'm not a thrill rider, so I skipped Space Mountain. And I skipped Stitch, too - I'd seen it on my previous trip and it's not a ride I'd do without my children. The Astro Orbiter makes us all sick, and I'll only ride the Indy cars on a cool day with no line - which is almost never!!!
So I saw all of Tomorrowland, including a snack and a music break, before lunch. Then I went to Adventureland and did the same thing. FastPass for Jungle Cruise, then through the treehouse, into the Tiki Birds and a 20 or so minute line for Pirates (which I appreciated because it was hot by then!!!)
If you work the system and realize you're going to have to get there early, then you can have a fabulous time!!!!