And on top of that, why would I visit your site to see who is paying the most for my attention? That's called advertising and this is a site devoted to mixing in paid placement with the voting public.
Why does this make it better than Digg / Reddit / Mixx / HN? I just don't get it and have no inclination to try hard to understand it.
How is it sustainable? After a while, all the top sites would be paid and thus of no interest to users who visit your site.