[travisglines]

I think a hybrid system would actually best. Otherwise posts that don't get many votes wouldn't update their score.

The best would probably actively update on votes and do a catchall operation on ones that haven't been voted on or all on a certain periodic cycle.

[bricestacey]

Also, if only updated periodically, the front page would "skip" so to speak every X minutes (exaggerated changes in rank), whereas re-scoring on each vote would allow smoother changes in rank.