San Mateo, Calif.-based Napster Inc. continues to grow in popularity, according to Media Metrix Inc. Usage grew from 1.1 million users in February to 6.7 million users in August, said the New York-based research firm. . . . The much-anticipated Version 2.4 of the Linux kernel will take at least another two months to complete, Linus Torvalds, creator of the open-source operating system, said Friday.