Mark wrote a similarly interesting article about the typography in Mad Men a couple of years ago too.
Also, a lot of the hand drawn layouts and designs pinned up on the wall in Sal's office are actually pages from Andrew Loomis's excellent book _Creative Illustration_. And most of the designs would have been more at home in the late 30's to mid 40's. But hey, in this case it's just wallpaper...
Still a great series, and as a child of the late 50's, early 60's I can say they get an amazing amount of details right.
(If you aren't spoiler free on seasons 1 through 3, don't look)
http://burndownblog.wordpress.com/2010/07/26/mad-men-font-fa...