For that matter, if you are getting a lot of traffic from Twitter, you may be getting even more than you thought.

Stan Pugsley, director of business intelligence for iCrossing says that nearly 70 of referral traffic from Twitter goes unmeasured, particularly if you are using web analytics tools like Google Analytics or Omniture.The problem is not with the web analytics tools, but with the Twitter applications like Tweetdeck and Twhirl that are not based in an Internet Browser, explains Pugsley. When a user clicks through a link in a tweet, those applications do not register a referring URL that can be picked up by the destination website. It appears that they are coming directly to the site.