Angela Grant has it right.
I think a "newscast" on the Internet is the inappropriate repurposing of TV to the Web. If I want to view a string of videos, I want them to be of my choosing. Produce enough video, organize them, make them searchable and shareable and the "channel" of programming will develop. The users will create the playlist.
I've looked at a lot of the Web newscasts and I have difficulty staying with them to the end, even if they are not longer than five minutes.
Do newscasts on news Web sites work for you?