Wow. For a minute I thought this online video fad would pass like the pet rock. But now ComScore ordains it as “officially going mainstream.” We at WillVieoForFood take a more cautious perspective. We’ll believe it’s mainstream when our grandmothe starts watching online videos. Since she’s dead, that’s not happening soon.

Here’s the press release that will be mentioned frequently in media coverage.

Highlight: Most noteworthy, however, was the popularity of online video, which continued to gain steam in July, as Youtube.com broke into the comScore Media Metrix Top 50 for the first time, debuting at number 40 with 16 million visitors, a 20-percent increase versus June. Video-mania also drove a two-fold increase in traffic to MySpace Videos, which had 20 million visitors, trailing only Yahoo! Video with 21.1 million visitors (up 28-percent from June).

“Consumers clearly view video as one of the most accessible, interesting and entertaining sources of content on the Web,” said Jack Flanagan, executive vice president of comScore Media Metrix. “The trends we’re witnessing indicate that online video is emerging from its infancy and entering the mainstream. Many publishers and advertisers are responding to this trend, which means advertising dollars will continue to migrate online where consumers can be targeted with efficiency.”

But can they be TARGETED? I don’t know of an online site that’s giving us fine-tune targeting. I’m not sure they even know their demographics.