The video iPod is not yet in Apple stores.
There is an Apple-hosted page on converting or creating video content for your iPod here. In essence, downsize it to spec using Quicktime 7 tools.
There is a page here which covers working with Tivo To Go content, importing and exporting it to and from the DRM the content comes wrapped in. In essence, use one of a few tools to save it as plain MPEG.
Unknown until tested are the undocumented features that may or may not be found in association with the S-Video out port on the new iPod dock; in particular, can the S-Video port support higher-resolution playback than the built-in screen’s native resolution of 320 x 240, quarter-VGA. Standard NTSC is 640×480, if I recall correctly.
Finally, will the iTunes store’s current podcast support seamlessly allow videobloggers to deliver content? Could an extant podcaster with a currently-supported podcast stream available through the Store slipstream video content to the new device?