It’s catching. After the BitTorrent announcement come this York Times story.

But with their latest creation, a Web video venture called Joost, Mr. Friis and Mr. Zennstrom, who were behind the file-sharing service Kazaa and the Internet telephone service Skype, are doing everything by the book. Revenue-sharing agreements have been signed. Licenses have been granted.

“The reason we’re doing this is because of our history,” Mr. Friis said in a telephone interview last week. “We know how these things work. And above all, we know that we don’t want to be in a long, multiyear litigation battle.”