Toyota Plug-in Prius on sale in 2011

In less than two years, Toyota plans to sell a plug-in version of its popular Prius hybrid to consumers. The company will want to fend off challenges to its green crown, which will be aplenty by 2011. Nissan will be selling its Leaf electric car. General Motors will have the Volt, to name a couple of them. But will there be enough buyers for all of these high-tech rides? Toyota will start