I wonder if this is Flash-based, like the existing Netflix preview feature.
The new immediate viewing feature differs from current services in that it does not require the often lengthy downloading of a large video file. The Netflix feature uses real-time playback technology that allows video to be viewed at virtually the same time it is being delivered to a user's computer. Following a one-time, under-60-second installation of a simple browser applet, most subscribers' movie selections will begin playing in their Web browser in as little as 10 to 15 seconds. Movies can be paused and a position bar gives viewers the ability to immediately jump to any point in the movie. In all, the instant watching feature requires only Internet connectivity with a minimum of one megabit per second of bandwidth. The more bandwidth a consumer has, the higher quality the video displayed, ranging from the quality of current Netflix previews to DVD quality with a three-megabit-per-second connection.