We did DW with our DS when he was 2.5 for 9 nights and he loved it! Like others have mentioned previously, you do have to pace yourself. As for naps, we tried to go without the naps the first two days and found that was just too much for DS... talk about cranky city, even in the Happiest Place on Earth! hehe
So we did nap breaks back at our resort, CBR, and found he was a much happier camper! Some nights he would stay awake until 10 PM (2 hours past his bedtime) and other nights he would fall asleep in his stroller.
Just play it by ear, and if your little one gets a little too pooped, just do a little more relaxation then actual park hopping. I'm sure you guys will have a blast!