I don't really know much (anything) about this service but based on it being the "twitter of video" I would like to point out that video requires more of my attention so the content they offer would have to be dramatically better to interest me. I can read an entire page of my Twitter feed in about 10 seconds skipping the stuff I don't care about easily. I doubt I can watch 10 seconds of Seesmic and get any value out of it. Of course the other obvious problem is you can post video to Twitter by pasting a URL in. Whoever dumped $12M into this company didn't anticipate users were intelligent enough to use URLs to point to videos or assumed that any video content automatically appeals to users more than text. Either way, wrong.