It actually demonstrates the curve that Kirk and Spock had to go through - from being, essentially adversaries over what to do (after the KM scenario), to having to work together at the end to destroy Nero.
Thus beginning the friendship.
'If the Apocalypse starts, beep me!' - Buffy Summers
'The sky's the limit.....' Jean-Luc Picard, 'All Good Things'
courtesy of Saquist