So, they split the difference: distributors will state forthrightly that DVD playback software is not officially released or supported, but will mention that some information about it is available on third-party sites.
Nudge, nudge, wink, wink.
This does not change the fact that as a US resident, if I watch a movie on my Linux machine on a DVD I either own, rent, or borrowed from the public library, I am going to be breaking the law.
I have a strong suspicion, however, that this situation may be rendered moot very soon.
The answer lies in the same reason the local Blockbusters in my city are starting to close down: streaming media. With pay-per-view movies on satellite and cable, and Netflix movies that will stream onto PCs, traditional DVD use is sharply declining. The Netflix model is especially intriguing: why buy a DVD at all, when ultimately I can get it anytime as part of a monthly subscription plan?
Of course, right now there is no Netflix service for Linux, because they're using Microsoft Silverlight as their video player, and even with Moonlight, Netflix playback is not an option because of Netflix's and Moonlight's opposing DRM stances. Amazon's Video on Demand is supposed to work with an up-to-date Flash install on your browser, but I've found it to be a bit glitchy.
If I were a Linux vendor, I would be looking very closely at getting such technologies working, and soon. Because the investment in development will be worth it--even if there's a license involved.
The reason why paying for a CSS license doesn't work for Linux software developers is that no one will pay a one-time purchase fee and there's no revenue to be generated from playing one's own DVDs. With a streaming subscription service, the latter argument is destroyed. Anyone who can come up with a working Linux client for one of the popular streaming services is going to be able to make some serious money, because a small cut of the subscription costs will generate a nice, steady stream of revenue.
This is something I will expect from the Android crowd, and soon. There's already plenty of streaming video apps for Android, so all you need to do is get an app to plug into an online video provider. And hey, remember those Blockbuster stores that are closing? Turns out the company is set to release an Android app soon. Given that any future tablet release from Google will likely run on Android, this could potentially resuscitate the once-proud video rental chain.
On the desktop side of things, I would suspect that Canonical, which is heavily pushing the cloud, might be working on a similar deal with one of the major video providers for a streaming Ubuntu client. This would be a perfect fit for their desktop- and cloud-centric approach, as well as be a source of revenue.