Going back through the comments on this blog, it's clear that many folks in the pro-domestic camp use the dramatically improved quality performance of their favorite automakers to do some cheerleading for the home team. However, Ron Harbour (who heads the organization that publishes the Harbour Report on manufacturing efficiency) states that simply having competitive quality is no longer enough, and that productivity isn't as a big of a deal, either. Instead, product now has to be compelling - and oh, yeah, price counts for a lot as well.
Harbour points towards the Mustang as proof, but of course other examples abound. Chrysler has had little difficultly selling its 300 sedan, and the comeback of Cadillac is one of the great industry success stories from the past decade.