The head of Toyota's Prius program thinks that Toyota will be able to sell as many as 1 million hybrids anually by 2015. Satoshi Ogiso, who was responsible for developing the original Prius, said that hybrids could sell as many as 2 million units by 2020.
Toyota Hybrid sales topped out at 690,000 in 2010, and many felt that if it weren't for March's earthquake and tsunami, the pace of sales would have accelerated even further. Prius sales (including the Prius c, Prius V and other variants) will account for half of hybrid sales.
Ogiso said that model line-up expansion would be kept under control for the Prius, but some expansion may occur. A sports car model was also hinted at, but appears to be some ways off.
More: Toyota Aiming For 1 Million Hybrid Sales By 2015 on Autoguide.com