Today's shootings on the Virginia Tech campus received scant coverage early in the afternoon on the broadcast networks, which, aside from special report cut-ins, stayed with regularly-scheduled programming.

But the horrific shootings were the only story on the cable news channels, which went wall-to-wall with coverage as they often do with such major stories.

As often happens, anchors allowed speculation to get ahead of the facts. A Fox News Channel anchor repeated a report (a rumor?) of how the shooter may have killed victims "execution style," but then acknowledged, "We just frankly don't know what happened."

MSNBC interviewed an expert on why males in their teens and 20s most often commit shootings such as this was interrupted by another voice that announced a revised upwards death toll.

All the cable networks used video from students' cell phones and personal electronic devices, often serving as the primary visual element in covering the story.

CNN labeled video recorded by student Jamal Albarghouti an "iReport," part of the network's citizen journalism program announced last August. The network solicits breaking news video (and other less newsworthy video on "your home office" or "your road trips") at CNN.com. The user-generated videos are posted online and in breaking news situations can end up on the air. (Those who submit video to the Web site are not paid per the "terms of use" on the site.)

A CNN spokeswoman said user-generated iReports have been used in previous breaking news situations -- including weather and last summer's plane crash that killed New York Yankees pitcher Cory Lidle -- but she said the video was used more extensively today.

The Virginia Tech shootings marked the first large-scale national tragedy that Katie Couric will cover since she became anchor of "CBS Evening News" in September. By 2:45 p.m., CBS had announced Couric will anchor tonight's broadcast from Blacksburg, Va. She memorably anchored coverage of the Columbine school shooting in Littleton, Colo., while anchor of NBC's "Today."

ABC announced "World News" anchor Charles Gibson, also facing his first large-scale national tragedy, will report from Blacksburg tonight.

More details in tomorrow's Pittsburgh Post-Gazette.