Playing CSS-encrypted DVD's on linux using any of the existing apps (xine, ogle, mplayer, ...) is only illegal in the US. For someone with a decidedly non-US name you should know that. Ofcourse, it won't be long till laws are approved in europe and Japan that contain comparable language to the DMCA (the EU law is drafted and will pass this year, despite it being even worse than the DMCA and drawing heavy protest from tech circles)

Also, CSS' focus is not on blocking people's ability to copy DVD's, after all, you can copy a DVD if you want to, because a DVD is just a series of bits, and you don't need to decrypt those bits to copy them. The real purpose of CSS is to stop people accessing and using DVD's in non-approved ways, like happened with music CD's. You can't skip past commercials on DVD's, you have to suffer with region coding (which stops parallel import, so the movie industry gets 100% of profits, instead of 95%), you can't make screenshots, you can't cut segments out of movies (both of these severely cripple any possibility of fair use; too bad it's not a right, or we could sue 'em).

There will also never, ever, be a commercial player for linux that will be publicly released. Why? To make a DVD player you need to get a license from the DVD-CCA, which among other things says that it must be impossible to make a screenshot. The open code of the linux kernel and xfree86 ensures that whatever trick any company would use to try to stop people from making screenshots would eventually be circumvented. Only closed source OS's, or integrated systems (which don't allow access to the system's innards) have the option of running a legal (in the US) DVD player, in other words.

Mind that the plan is to switch music CD's over to music DVD's eventually, which will no doubt have exactly the same problem, and have no legal players on linux. Ever.