do you guys take logs of both sides, so you don't have to keep updating the scores of all the previously posted items? I mean, if all that matters is how big the scores are relative to one another, then A > B <=> log A > log B (since A and B are positive). You'll just have to add a G*log(T+2) to the log(P) for new items, which can go on for a very long time. ... T is the time since some arbitrary point.

I think I may have just reinvented the way reddit does it :P