I agree that there's a lot of fluff on Reddit, but I don't think I agree with your solution. I find a lot of good, technical comments end up quite a way down the page in more detailed discussions between users who are more interested in the subject matter than having a conversation (or having their joke voted up the page.)

Really, I wish Reddit had something closer to Slashdot's moderation categorisation to filter on. Filtering out "funny" comments would be nice. Ignoring votes cast by people who just want to register their agreement or disagreement would be an incredible, impossible goal.