In "Alec in Huluwood," Hulu.com's first-ever Super Bowl TV spot, Alec Baldwin describes how the streaming video site, a joint venture between NBC Universal and News Corp., will allow television to fully, finally succeed in turning our brains to mush.

It's debatable, of course, whether online episodes of "Family Guy" and "Colbert" rot our crania more, or faster, than quick-hit clips of dramatic chipmunks and skateboarding cats. But this much is clear: The two kinds of video owe their success to two very different demographic...