The parks are not crowded, but the restaurants can be a nightmare. Priority seating to popular spots were impossible to get when I went and people were pitching fits because they weren't able to get seats. This happened everywhere from the hotel concierge desk trying to find restaurants all the way up to the restaurant podiums. I was very fortunate to have priority seating reservations, but angry guests dampened the experience somewhat.
If money isn't an issue, definitely go later. The weather is cooler in October (not to mention Food and Wine Festival) and if you time it right, the crowds are about the same.
Just one opinion...
