Anyone who watches news or music video networks on television is constantly hit over the head with the word. Newspapers and magazines are brimming with stories about it. So it seems almost unimaginable that 69 percent of Americans still “didn’t know enough about Twitter to comment on the service.” The report in the Los Angeles Times might understandably trouble some of Twitter’s most passionate advocates. It seems obvious, however, that the study reveals that there’s still enormous room for growth.