I'm so sick of this argument: "Is podcasting audio only?".
Ugh. I can think of one reason why the answer to this question should be no, and that is that podcasting is a crappy name.
That said - there's no reason for multiple words to describe the same technology. Wether it be mp3 audio, wmv video (MS Channel9), jpg photos (iBod), iso images, exe updates (aka "appcasting"), or any other file type, they can all be delivered via RSS enclosures. They can all be automatically cast to a mobile device.
Yes, it would be pointless to cast these to an iPod. Who's fault is that? Apple.
Where can I cast wmv's or jpg's so I can actually use them? Windows Mobile, you say? You mean my pocket PC has Windows Media Player pre-installed on it? And it plays more than just audio? Wow! Great! This should NOT be a newsflash.