Does anyone know how "The Weather Channel" distributes the regional
> forecast information (as seen during the "local on the 8's" portion)
> to the local cable companies. Is it data in the vertical interval of
> the TV signal, or do they use internet connections (broadband,
> dial-up), or some other communication channel?
None of the above. It's one-way IP over digital satellite (using multicast IIRC). They have some sort of a backchannel, but I don't remember what it was. The one box also handles all of the video (de-)compression. (It's a PC running FreeBSD, for those to whom this is meaningful, with specialized satellite and video hardware.)