We just received word from the Tech Report that they've posted an update to their Radeon HD 2900 XT launch article in an attempt to clear up an issue related to the R600 GPU's UVD support, or lack thereof...
"The UVD logic handles the CPU-intensive bitstream processing and entropy decode acceleration portions of the HD video playback pipeline. These are the most notable video decode acceleration capabilities that would separate the Radeon HD 2900 series from its direct competition, the GeForce 8800 series, if the HD 2900 XT actually had them. Turns out it does not. As the email states, the video playback capabilities of the Radeon HD 2900 XT are essentially similar to those of the previous-gen Radeon X1950.
So the essence of our correction is that the Radeon HD 2900 XT doesn't offer robust acceleration of HD video playback and will not likely reduce CPU utilization or power consumption substantially during high-definition video playback versus a GeForce 8800. We still intend to follow up with testing, but the lack of UVD logic on the GPU resets our expectations dramatically."
We (I) was also under the impression that R600 had the UVD engine built-into the GPU, partly because it perfomed well while playing back an H.264 encoded movie trailer. That trailer wasn't encrypted, however. We have since updated the wording in our article to make it clear that UVD is part of the Radeon HD 2600 and 2400, and not the current generation HD 2900 XT.