Alright - I must be new here, but here goes:
The distinction between comments that get modded as Funny and those that get modded as Offtopic seems to be indistinct at times.
Given the fact that most, if not all comments that are meant to be funny are more or less not exactly on topic, this seems strange. Anyway, to me, a comment is only offtopic if it has nothing at all to do with the story. Humorous comments at least poke fun about something concerning the story. I have even seen successful 'funny' comments that simply choose to make fun of a previous comment while completely deviating from the topic of the story. I have also seen (and *ahem* posted) comments in this vein that have been modded down as Offtopic.
I am not quite why some of these comments go up while others go down. This is one of the great Slashdot mysteries. I think the most likely theory, however, is that people tend to Offopic-mod 'funny' comments that they don't think are that funny. If this is so, I find this inexplicable for a couple of reasons.
The first one is that this is a waste of mod points, in my view. If you don't think something is funny, you should leave it untouched, unless it is somehow offensive or definitely completely Offtopic. You shouldn't waste mod points going after these comments. Are they really that unfunny that they should be resigned to the bottom of the thread?
The second objection is that being modded Offtopic causes the author to lose Karma, which is obviously bad (duh). Couple this with the fact that being modded Funny does NOT give the author any Karma, this basically, well, sucks. This makes people less inclined to post humorous, wacky comments, and can even make people nervous about doing so. I think that something could and should be done about this.
Well, just my two cents worth of gripe