In 2007, transmission of full-motion digital television signals to mobile and handheld devices was proven technically feasible. Leaders of the broadcasting industry came together to make mobile digital television a reality; they formed the Open Mobile Video Coalition (OMVC) to accelerate the development and rollout of mobile DTV products and services, maximizing the full potential of the digital television spectrum.
Today the OMVC truly represents the industry, with members that own and operate more than 800 commercial and public television stations nationwide.
There was a lot of publicity of MDTV at the CES 2010 recently in Lag Vegas, USA. Here are few Youtube clips on MDTV.
There is also an interesting OMVC Mobile TV Use Cases document available here.