I wouldn't worry about that if I were you Andy. We know, and you know - you like sharp pointed pieces of metal. And I'm sure you're capable handling one. It just shows the opinion of (as Marts put it) Small Minded & Vindictive.
The reputation system is a good thing to have IMO, although I agree it's misused by some people in some situations (and if it's found out who do this, they should be banned IMHO, as I see it as some sort of anonomious flaming). As mentioned by others before me, I would vote for the same system as used on BB. Purely because the name of the person giving rep. is added.
I seldom give a person rep. Only in when I find it a really good post / it's of some great use for others. When I give it, I always put my name in it, as I find people should know by who the rep is given. Not because I expect rep back from people. But just so they know their post was of use for me, and they taught me something I didn't knew before.
Never give negative reputation, as I think it's not fair - eventhough I'm allowed to give it if it's c**p in my opinion and of absolutely no help whatsoever / or just wrong info. I find it's better to comment the post to teach the person, rather than blunt "punishment" by neg. rep.
Only gave negative rep to one person - but gave positive criticism, and at the moment the posts by that person are really growing / more mature. Before they were just ****.
My 2 cent