Twitter Traffic

Who's to believe when people report on traffic to Twitter? Compete.com says it's 21.2M unique visitors; comScore says it's 22.3M; Twitter says it's 180M. Given, Twitter does have access to the most accurate data, and they're counting the millions of people who use Twitter by other means (mobile, TweetDeck, off-Twitter Web sites, etc.), but that's a huge spread.

Twitter recently stated that 75% of its traffic comes from third-party apps like Tweetie, which, incidentally, Twitter just bought. While I'm not sure if that 75% includes traffic from sources like other Web sites -- let's assume that it does -- that should mean that 25% (or 45M visitors) of its traffic comes from Twitter.com. So still, there's a wide spread -- more than double -- between what Twitter says their traffic is and what folks like comScore and Compete.com say their traffic is.

Are these Web site traffic reporting services that inaccurate? Is Twitter reporting visits and not unique visitors? If so, that's called fudging the numbers. Consider, Social Media Graphics recently reported that 79% of Twitter accounts they analyzed are not true Twitter users, as they define it.