The Electronic Frontier Foundation's (EFF) Seth Schoen has posted an article on the upcoming - as he calls it - DRM features of Flash Media Server 3.
Make of DRM as a technology what you like but I think the author has missed the point here, or does not understand the purpose of RTMPE, the new encrypted flavor of Adobe's Real Time Messaging Protocol. FMS3 doesn't actually apply any kind of DRM to the video content itself, it merely secures the transmission and thereby circumvents content from being intercepted in transit, a process that's similar to the way that your credit card information is being transmitted to a payment provider when you buy things online - anyone listening in on that transmission will see just garbage that would take years to decrypt.

The author also raises concerns that 'remixers who find and use tools that break the Flash Video encryption could be sued, even if their transformative creations would otherwise have been fair use'. These concerns are unfounded - many sites, including all the consumer facing properties which deploy Flash video progressively, are unlikely to move to FMS anyway, hence will not use encryption and will continue to offer remixing facilities .

Lastly, encrypting the delivery channel does not sound like DRM to me, it's mere access control. Using secure transmissions and token based authentication, this has been done already. All Adobe did in regards to FMS3 is make the SSL-style encryption easier to use and lighter on system resources by using RTMPE.