Matching the stride of a fierce competitors such as the BMW 3-Series is among the toughest tasks in the automotive business, and the 2006 IS seems to measure up to the challenge. With its new, exciting, emotive design, more model choices, two new powertrains on an all-new platform, and a plethora of virtually transparent technology, the IS has tossed down the gauntlet to its import rivals. We'll see who, if anyone, picks it up with a ready answer to this intriguing new luxury sports sedan.