Hi Matt

It's entirely down to the training centre as to the textbooks and materials they use during the CELTA. I remember when i did my qualification the first observed teaching i did was a listening exercise which comprised an interview with Gloria Estefan! It was a while ago that i did my CELTA but it certainly wasn't the 1980's!
Headway, Cutting Edge, etc. are still popular and provide a well structured fairly easy to use course. They also consistantly print new editions to ensure the topics and general feel of the books move with the times, ie. you won't find any Gloria Estefan interviews in them - shame!
You might also choose to supplement these courses with activities and ideas from books such as Reward or any of the series of Cambridge Handbooks for Language Teachers.