Of course this may be a 'black hole' where complaints go to die, but I've recently found this website:
http://airconsumer.ost.dot.gov/escomplaint/es.cfm
Personally, I am VERY tired of the runaround Continental typically gives me when they experience a problem - from now on, EVERYTHING is getting sent to this web form. The more complaints for Continental the better off we may be - and if it doesn't help us, well... it certainly won't hurt!