One of the best fanfic takes on this I've read (which is actually set the next day) has several teachers having a conference with the boys present to discuss punishment, with very little said about the genuine risk to a student's life. The end result (which seems pretty likely) is that Sirius loses 100 points for putting a student in danger, James gains 50 points for a heroic rescue, and Snape loses 30 points for being out of bed. Net result, as Snape sees it, is that his life is worth 20 points. The fic ends with Lucius (written pre-OotP) feeling genuinely very bad for Snape but also being quite pleased because it will make recruiting him *so* much easier.

And so many Slytherins joined the side opposing Dumbledore because they're innately evil and the Gryffindors are innately good. Riiight.