I first saw a demostration of OLED screen technology at CES2003.  It was demoed for usage in cellphones and portable devices and promised to be one of the keys to lower power consumption (longer battery life).  It looks like the technology is still a few years off from commercialization in TVs (I think there are a few cellphone handsets that have OLED screens).  Here’s an article from CNET that gives a nice summary of the current status of OLED TV.