News Web sites are starting to look a lot less like newspapers and a lot more like television.

CNN.com and ESPN.com are featuring video much more prominently on their home pages, often prompting visitors to press play before they begin to read. Even The Wall Street Journal has moved its video player front and center with a twice-a-day live newscast on WSJ.com.

A major reason is commercial. At a time when other categories of advertising dollars are shrinking, video ads are booming. News sites are adding more video inventory to keep pace with the demands of advertisers, and benefiting from the higher cost-per-thousands, or C.P.M.’s, that ads on those videos command.

The attention to video mirrors changes in how consumers are experiencing news. Major events — be it the presidential election or the death of Michael Jackson — bring a surge in video stream viewings by new users, and each time some of them stick around.

“Every watershed event leaves video more popular than before,” said Charles W. Tillinghast, the president of MSNBC.com, a joint venture between NBC Universal and Microsoft.

K. C. Estenson, the general manager of CNN.com, a unit of Time Warner, said that “people are using the Internet in a different way now.” He added, “With broadband penetration becoming ubiquitous and more and more sites having this easy capability, people are expecting video to be there.”

Media companies typically do not break out figures for video advertising, and certainly the video revenue pales next to search and display advertising. But the growth has spurred investment and interest in video production.

More ...