Stayed at this resort for a conference and spent a lot of time eating at JD's! Servers seemed very attentive and pleasant, food was fine quality, price was reasonable, and the atmosphere is great. There are huge TVs all around showing whatever sports events are on at the time, buttery and salty popcorn at every table -- pretty good experience all around. I didn't have a bad meal, though I thought that their monthly special (a Hawaiian bison burger with sweet potato fries) was the winner of the weekend. It's not likely that I'll be back to the Scottsdale Plaza unless I come to another conference, but if I do, I'll have no problem eating at JD's.
EDIT: Updated to drop from 4- to 3-stars because they don't have the Pac-12 channel in the sports bar, but they do have it in all the hotel rooms. What??!!