I have bigger HDMI-CEC problems..
CEC seems to work, it shows up in my TV's CEC menu (Samsung LN46B650), so it's labeled "Anynet+", and selecting it will change the input and wake up the WDTV Live. However, none of the other buttons on the TV remote seem to do anything after it has switched to the WDTV Live. I have to use the WDTV remote or a remote app on a smartphone to control the WDTV. Does anyone else see this behavior on Samsung LCD TVs?
The only other CEC device I have is a samsung BD-player from the same generation as the TV, and unsurprisingly, CEC works perfectly there. So, did samsung do some weird proprietary CEC stuff, or is there a problem with my WDTV, or both?