Just to be clear-- the feedback that has a grey box next to it doesn't have to be from newbies. People who's point total is low-- for whatever reason-- cannot impact your over-all "reputation" either, resulting in the grey box and no change in your total. As has been pointed out before, the more points someone has the greater the "impact" of them giving you feedback will be. i.e. one person may give you feedback that will add 6 points to your total while someone else's feedback could give many more points than that. It's a bit complicated, but it is designed to make sure new or "low point" old members can't impact your total equally. Also, "approvals" count much more than "disapprovals."

BTW, one thing I just noticed. The little "gems" that appear next to your post-count in posts; there is the dark grey "member has disabled reputation" gem-- which a lot of people have and then there is a light grey "gem"-- which appears to mean that the member's point total is very low (or even negative) but that they haven't disabled reputation feature (yet ) The more I see the system (not including the comments,) the more I like it...