This was one feature I never got working until just a few minutes ago, even though I tried a couple of times !
Thanks to sebz, and a shared Google Reader item, the following article explains you how to do that !
Since it is really simple, here are the two commands you need to type in a terminal to get your DVDs running :
Right after that, insert your DVD in your drive, and you should be on the road for some classic DVD watching on your favorite free open-source OS !
For the record, I even successfully played the DVD from french comic Jean Marie Bigard, which was impossible on Windows XP !
PS: Sorry Vince, you were right, it IS simple to play DVD … Once you know the correct configuration 😉