Live Streaming Podcast

No: at least not in iTunes. You could create a web page with streaming episodes, and call that a podcast, which would be fair enough: but the iTunes Store requires a direct link to a payable file.

When people subscribe to a podcast their iTunes application downloads the episodes and they then reside on their computer to play at will. If they leave iTunes running new episodes will be downloaded automatically in the background. But they must be actual files: iTunes can't handle streamed media.