Factor 5's American division may have gone belly up, but models of a project called "Flight Project" have been released onto the Internet, and it could have been the Pilotwings they were making for GCN and then Wii.
http://www.unseen64.net/2009/05/14/f5s-flight-project-wii-prototype/ (http://www.unseen64.net/2009/05/14/f5s-flight-project-wii-prototype/)
I think it looks pretty cool, and it still might have a chance for release if it's picked up by some other company.