From movie director John Landis in an online chat today:

Pittsburgh, Pa.: Being a 30-something, I’ve grown up with a lot of your great movies so I was wondering, as a great crafter of comedies, what current or recently released films of the past few years have made you laugh?
John Landis: I enjoyed Shawn of the Dead and although I have not seen them, I’m very happy for the success of “40-Year-Old Virgin” and “The Wedding Crashers” because they are R-rated. The studios have been leery of R-rated films in these creepy Bush times, so the success of those films is a hopeful sign. Every film I ever made that grossed over $100 million (Animal House, Blues Brothers, Trading Places, Coming to America) were all R-rated. There’s nothing in The Blues Brothers I wouldn’t let a 10-year-old see, just some profane language.