Update: After 58 years, Pinnacle Peak Patio is closing its doors in December 2015, so get in one last hurrah! Whether it's your first visit or your umpteenth, it's well worth a drive out there.
RECOMMENDATION:
PPP has a "No Necktie Policy." If you are seated with a necktie, the waiter cuts it off using scissors. So... stop by your nearest Goodwill before you go and buy their cheapest and ugliest tie for $1.99. If you go on a date, with a group, or with kids, it'll make the experience even more fun.