Advertisers to Twitter: get more users

As hard as it may be to believe, 200 million users just isn’t very impressive to some advertisers. They’re telling Twitter to get more users if they want their money.

For some advertisers, 218 million people isn’t a big enough audience. That’s their message to Twitter Inc., which Thursday detailed plans for an initial public offering.

Ad buyers say that the short-message service will need significantly more users, and a bigger sales force, to win more spending from their mass-market clients.