On April 22, Microsoft notified you that as of August 31st, 2008, we would be changing the level of support for music purchased from MSN Music, and while your existing purchased music would continue to play, you would no longer be able to authorize new PCs and devices to play that music.
After careful consideration, Microsoft has decided to continue to support the authorization of new computers and devices and delivery of new license keys for MSN Music customers through at least the end of 2011, after which we will evaluate how much this functionality is still being used and what steps should be taken next to support our customers. This means you will continue to be able to listen to your purchased music and transfer your music to new PCs and devices beyond the previously announced August 31, 2008 date.
Microsoft continues to recommend that you back up your music on CD or hard drive along with other important data.
As noted on arstechnica, this change comes a couple of months after MSN first announced that MSN Music customers would have until the end of August, the scheduled time when the MSN Music authorization servers would shut down...
"This, of course, was bad news to MSN Music customers who bought music from the service before the company launched the Zune Marketplace and decided to ditch the old store. It furthermore served as a painful reminder of how drastically DRM ultimately limits your rights to use content you have lawfully acquired. Companies that control various DRM schemes, as well as the content providers themselves, can yank your ability to play the content which you lawfully purchased (and now, videos) at any moment—no matter what your expectation was when you bought it."
IMO, it's good to see that the MSN Music team listened to customer feedback. It's unfortunate that the extended period benefiting MSN Music customers "through at least the end of 2011" didn't happen from the beginning. Originally an avid supporter of Rhapsody and now Zune's subscription service, I acknowledge that there can be issues with DRM. But I've found that any limitation is far outweighed by the benefit of an all-you-can-eat music subscription: as I noted a couple of years ago, the subscription model vs. digital purchases has changed how I buy music: I find that I purchase more CDs from a more diverse set of artists than I have in prior years...
"The new subscription packages let me legally "try before I buy" and I am buying CDs from artists I would have not easily heard previously."
And the quality of subscription music is more than OK for casual listening... I take it with me on my Zune and my tried and true Sandisk Sansa m240 for walks and workouts. For critical listening over the stereo system, subscription music is fine for parties and background music at home... but I'm still inclined to buy the CD for more critical listening.