For a long time I've been skeptical of the role of video online. I always felt like people just liked watching videos on their television sets - not their computers. Evidence about online video use seemed to support my anecdotal conjecture.

But the last few months have delivered some major blows to my theory. Apple introduced the video ipod and started selling television shows through the iTunes store - and people took to it in droves. At the same time, YouTube seems to have become completely ubiquitous, allowing video publishing and video sharing to completely explode. And I was with a friend recently who now watches the Daily Show via his cell phone every day using Verizon's V-Cast.

Given the emerging ways of delivering video - vcast to mobile phones, ipods, TiVo/DVR, web-based services like YouTube - what's the right length for video? or is there even a "right" length? Does anyone over 30 (i.e. likely voters) watch online video? How do they consume it? Does it affect their attitudes and actions? Can online video be used effectively for political persuasion?