The new Prius/Why do cars always get bigger and heavier?

[Stew-2]

"The engine behind the batteries will be increased from the Yaris' 1.5-liter four-cylinder up to the Corolla's 1.8-liter engine. The car will be a half-inch longer and about an inch wider."

From:
http://reviews.cnet.com/8301-13746_7-10015459-48.html

Why does this happen with every design cycle? We had an email thread going about this topic a little while back, here it's happening again! With the Prius no less! I just don't get this, is the Prius eventually going to end up a full size sedan like the GM hybrids that get a whopping 32 mpg?

[Stew-2]

Ooops, I created this in the wrong category. Should be in the hybrid area.