Good question. I've always thought people with absolute pitch can immediately "feel" the pitch, as in, "that's a C!" Meanwhile, I still need to infer through internal reference points, as in "that's a C, because the soundtrack of Bob-omb Battlefield from Super Mario 64 begins with the same note, which is a C!" My way takes 2-3 seconds, while those with absolute pitch don't need to extrapolate/infer.