In this video from the OCaml Users Conference back in April, Xavier Leroy explains the 8 new features in OCaml 3.12. As I said elsewhere, none of the features are earth-shattering, but they make a great programming language that little bit nicer.
The bit where he discusses the new features starts at around 11 mins 50 seconds in.
Direct link to the video site (also requires flash)
Thanks to Sylvain Le Gall for organizing this.