Yeah, certainly the 'high = bad' thing is something we grappled with (and still do). The site is a sister-site to a consumer-complaint/petition website (http://www.groubal.com/), hence we're more interested in measuring/highlighting who is doing 'badly'. But yes, this could be done in a more intuitive way (showing the 'bottom' of a graph that had the axis in the traditional orientation, for example).

'Lowest Satisfaction' => 'Most Disatisfied' or 'Highest Disatisfaction' or 'Most Complaints'

'Customer Satisfaction Index' => 'Customer Disatisfaction/Complaint Index'

'High scores are negative' => 'High scores indicate high disatisfaction' or 'Increasing scores indicate increasing disatisfaction'

High scores bad, low scores good.

Link 'high' and 'increasing' with 'bad' and 'disatisfied' a little more explicitly and consistently, since most people make the opposite association.

Better yet, just flip the Y-axis. I'd think that it would be easier to get a company to pay to improve upwards. Do you really have to match the sister site?