The four-headlight theme introduced on the previous-generation E-Class is now the company standard, but it has been refined further in the mid-life freshening of the 2007 car. Up front, the bumper and radiator grille now have a pronounced V-shape, the spoiler is lower, and, for a striking effect, the twin headlamps sport transparent louvers over their top sections. A finishing touch is the white LEDs used for the parking lights.

The front end's new look for 2007 is carried to the rear along deeper side skirts to a new rear bumper and taillight configuration. Along with the new, more aerodynamically shaped single-strut rearview mirrors, the changes keep the E-Class looking fresh and youthful, yet elegant.

The current E-Class design introduced many innovations not necessarily apparent to the eye. This was the first Mercedes sedan to use aluminum body components extensively, starting with the hood, front fenders, trunk lid, front crossmember and front subframe. Aluminum is lighter and stronger but more expensive than steel. Aluminum amounts to 10 percent of the body's weight. About 37 percent of the total is modern high-strength steel alloys.

From the aerodynamic perspective, the E-Class is one of the slipperiest sedans extant. Its 0.27 coefficient of drag, identical to the 2006 model, is a benchmark for sedans and helps minimize wind noise and maximize fuel economy.

The E-Class wagon, this year available only in E350 and E63 AMG versions, will never be mistaken for anything but a wagon. Nonetheless, it is impressively sleek, and some critics find the tear-drop taper of the rear roof more aesthetically pleasing than the trunk deck on the sedans. The exterior revisions on the sedan apply to the wagon. The wagon has been fitted with a larger center brake light. The wagon's added cargo-passenger flexibility is welcome. If the E350 wagon is too stodgy for your taste, there's always the new E63 AMG wagon.

The E63 AMG sedan and wagon look meaner than the other E-Class cars. With their lower body cladding and 18-inch wheels, the E63s look racy and aggressive. As is often the case, the body add-ons add slightly more drag, if you can call a super slippery 0.28 Cd more drag. The aerodynamic aids are for downforce, to improve grip in fast corners.