The Milwaukee Journal-Sentinel says "it's about the same size inside, with the same trunk space, as the full-size, rear-drive Ford Crown Victoria or Mercury Grand Marquis, although it's nearly a foot shorter for easier parking."
http://usnews.rankingsandreviews.com/cars-trucks/2008-Ford-Taurus/
http://usnews.rankingsandreviews.com/cars-trucks/2008-Ford-Taurus/