The only way you’ll know if your communication program is effective for your own employees is to obtain their input through a research project.
Video
Best Practices for Internal Television
What I have seen in “best practices” varies quite a bit from satellite broadcasts to all locations, to videos tailored to different job functions, to Web casts that include not only picture/sound of an executive being interviewed, but also windows on the screen to either submit a question to the interviewee or to participate in an ongoing chat with other viewers on everyone’s reactions to what is being said.