Kubuntu 13.04 64bits
I don't seem to find this exact bug listed so I'll report it. In CYCLES, the auto-refresh option for video textures is not working correctly. First of all, it doesn't work during animation playback, not in material mode, nor in Texture mode. Then, the only way to see it refresh is to select the object and then scrub the timeline... but it only works with the active selected object, not with every object in the screen.
If this gets fixed, might I suggest that the addition of Blender Internal's "match movie length" texture button, would be a great idea for cycles too?