PowerDVD correctly plays 3D Blu-Rays as well as my own 3D (side-by-side) videos taken with my LG Thrill and my earlier HTC Evo 3D. Occasionally, a home video is not automatically detected as 3D (e.g., if taken in very dim light), but I can then manually set the video to play in 3D. Unfortunately, there is no such option for YouTube videos.
How are other people getting YouTube yt3d videos to play correctly in 3D?