cyph9r offers us the very first score run in Halo: Reach with a run of Exodus with 92,691 points!
In his own words:
I did this on Heroic with all the skulls on besides Blind and Mythic.
I got a few nice combos and multikills in the landing pad room and shot down a few banshees.
Hijacking the wraith made killed the last wave of brutes and chieftains a lot easier.