Twitter Grows 3712% Year-on-year in the US

According to Nielsen Online, Facebook is the #1 social networking site by total minutes spent in the US in April 2009.

Source: Time Spent on Facebook up 700 Percent, but MySpace.com Still Tops for Video, According to Nielsen , 06/02/2009
This table shows that Twitter increased 3712 percent year-on-year. Twitter is rapidly growing.