On this point sir, I could not agree with you more.
Ideally the up/down voting system within the forums would be culturally accepted as a way to vote quality up and crappy down. So someone could make a point you disagree with, yet you give them an upvote because it was so eloquently stated.
I think that is a pipedream though to be honest with you, people get angry behind their keyboards and do stupid things. It is absolutely my intention for the voting system to be used this way and I encourage you to assist me in spreading the good word.
Now, in terms of linking it to Karma, it might actually take away some of the rage-karma changes. Right now, if someone pisses you off, you go in and change them from a 10/10 to a 1/10 - and that fluctuates the system like crazy. The member-to-member Karma is a multiple so it ends up making a huge difference when you skew the system with that much anger.
The way we calculate a 1-10 rating using up/down votes is actually much more accurate in aggregate. So you'd simply rate people's posts as you see them, and then overall we'd generate your 1-10 score against that member without your direct control over it.
So in the end, the wins we'd get from being able to use math against granular data outweigh the one-time rage issues of downrating posts. In actual fact, it actually helps beat it.