Would you like fries with that? Some pretty reputable news sources are running with a story that Toyota will be releasing a super-sized Prius by the end of 2010. The Prius XL will be in the form of a wagon or small SUV - probably similar to the size of what the RAV4 used to be. The Prius XL will also be the first hybrid that Toyota produces with a lithium-ion battery pack in place of the NiMH pack used in the 2010 (and previous) Prius.

Toyota's been sneaking around on Nickel-powered Priuses behind their back, performing a 3 year, 126 car road test of Lithium Ion batteries in the 2006 Prius.  The results?  The cost doesn't justify the "small" fuel economy gains.  Here are all the details from Bloomberg: