Yesterday, I posted some info about the upcoming production version of the Prius C Concept (earlier post), which was shown at the Detroit Motor Show, and now I've some more info from the latest BC issue. BC claims also that the Prius C will achieve a fuel efficiency of 44.0 km/L and the dimensions mentioned are exactly the same as the ones published by Mag-X.
From what I could make out of the text, Toyota will use a modified version of the current hybrid system, in order to reduce the cost and maintain the proven reliability. The car will be able to accommodate four adults and as you can imagine, don't expect any thrills with just 76 ps and 11.7 kgm of torque. It is expected to cost around 1,590,000.