Centova Cast is a control panel for ShoutCast and IceCast streaming servers. While ShoutCast and IceCast do both support video, they do so in very limited capacities. Centova Cast will not stop you from using their video capabilities, however you'll need to provide your own live video source (i.e., it won't tie into Centova Cast's autoDJ).
While IceCast is indeed video-capable, it only streams in Ogg/Theora format. Theora itself is a technical marvel, but the problem is that no common media players support it out-of-the-box. Thus, the only way for a listener (or viewer, rather) to tune into your video streams would be to install something like VLC, or plugins for RealPlayer, or a custom DirectShow filter. Realistically, that's just not practical for the vast majority of the non-tech-savvy public, and it would be a support nightmare (both for us and for our clientbase).
ShoutCast DNAS also supports video streaming, but only in NSV format, and again, NSV is only supported by WinAmp. WinAmp definitely has a broader clientbase than VLC, but it's the same situation -- regrettably, the vast majority of the public has only Windows Media Player installed, and occasionally RealPlayer, and usually little else.