Ed Felten has posted a review of Google’s DRM scheme over at Freedom to Tinker. Bottom line:
Google’s DRM, like everybody else’s, can be defeated without great difficulty. Like all DRM schemes that rely on encrypting files, it is vulnerable to capture of the decrypted file, or to capture of the keying information, either of which will let an adversary rip the video into unprotected form. My guess is that Google’s decision to use DRM was driven by the insistence of copyright owners, not by any illusion that the DRM would stop infringement.
The article also includes a good explanation of the tradeoffs involved in building the kind of system Google has constructed.