I prefer pizza hot, though cold isn't bad. When I have leftover pizza I heat it up slightly. Just enough to where I get a nice mix of hot and cold on the same slice.
Hot pizza is great. You can feel the sweet taste tingling in your taste buds and that flavor travelling in your taste buds. I will never ever eat a cold pizza, that'll mean my pizza fantasy would be broken.
I can eat hot or cold pizza, but they cannot be reheated pizza. Leftovers are fine if they're cold...just please, do not reheat it. I find that the microwave/oven basically erases some of the taste from the pizza whne you do reheat it. Maybe I'm crazy? Who knows.