I just got an Audigy card and I don't know what you all are talking about. It functions the same as my 4 SBLive cards for all media. If you read up on that protection scheme, it is only for WMA format files.
So sites that want to provide things with Microsoft's WMA format will be able to put in protection. They can in no way do anything to the mp3 or cd standards as they are right now.
The support in the hardware just means that if someone creates a WMA format file with the authentication in it, this sound card will actually support it unlike most other sound cards right now.
Don't all freak out
This card makes my Klipsch 5.1 speakers sound even better now (hard to imagine), even better than my 'old' SBLive Platinum 5.1
As for the Audigy compared to other make cards, I don't really know how they size up. I buy SB cards simply because for the audio work I do and game testing/experimentation. The firewire and midi/spdif connections are perfect for what this machine is for esp. for the price.