I was under the impression that config.lua is where main.lua gets the display.contentWidth, display.contentHeight values from to begin with?
Either way, hopefully this has helped someone somewhere fix a bug 
It does. display.contentWidth and display.contentHeight are populated from the width/height values in the content table in config.lua. The issue is with display.pixelHeight and display.pixelWidth. In the main trunk, these two values are picked up before config.lua is processed. In the current G2.0 build, they are populated after config.lua is processed, so we can’t calculate the aspect ratio off of those values. This should be addressed in the next build as .pixelHeight and .pixelWidth will be set prior to config.lua’s processing.
Ok I get it now, that also explains why .pixelHeight and .pixelWidth appeared to be correct when I printed them.