Now that Twitter has gone public, the company needs to prove to its shareholders that it can generate money. As it stands, only about half of marketers using Twitter are satisfied with the service. One web strategist, Tim Jensen, even went so far as to advise his clients against using it because of the clunky advertising interface and the limited functionality. However, ever since the new retargeting tool was introduced, marketers can segment ads based on specific products and services. This is a major step towards turning Twitter into a viable advertising platform.