The video should be subtitled, since the audio doesn't pick up the boy's poorly-vocalized responses, but we'll trust them on the details. It's an impressive talent.
Generally, absolute pitch implies some or all of the following abilities, achieved without a reference tone:
Identify by name individual pitches (e.g. A, B, C♯) played on various instruments.
Name the key of a given piece of tonal music.
Reproduce a piece of tonal music in the correct key days after hearing it.
Identify and name all the tones of a given chord or other tonal mass.
Accurately sing a named pitch.
Name the pitches of common everyday sounds such as car horns and alarms.
(Reposted from 2015 because it's an awesome talent)