Looks pretty dated and old fashioned. Like the above poster said, it's a very conservative style geared towards the 60+ crowd.
The tail lights are totally boring. Although I personally happen to think the BMW 5 series tail lights are the most beautiful in class, so I'm probably biased. Nothing really comes close.
The only Mercedes design I've really liked in the past is the previous SL design. The current SL looks like a total whale with an elongated, bulbous nose.