I have just noticed that upvotes for comments yield +1 in reputation. Do you think it is justified cor comments to the give identical yield as upvoted questions and answers? I think, if at all granted, the credit for a comment should be less than an answer, but I don't see how this could be approached without having fractional reputation scores.
it also seems to be encouraging comments. or maybe I'm just noticing them more since they appear in "Recent".