An all-new S60 is expected for the 2010 model year. The S60 marked a clean break for Volvo from the boxy design that many stereotyped the brand with in 1980s and 90s. Its design by Peter Horbury built upon the styling of the S80 and was the most marked departure from traditional Volvo styling since Horbury joined the firm in 1992. Accordingly, Volvo marketed the car as heralding a Revolvolution. It was built upon Volvo P2 platform, which was shared with three other Volvo models: the S80, the V70 and the XC90.
The S60 was refreshed in 2005. The exterior was updated with body-colored side moldings and bumpers, as well as new headlamps. The T5 engine received an increase of 10 bhp. 2004 Volvo S60R First introduced in 2003, Volvo's S60 R boasted AWD (Haldex) mated to a 300 hp / 295 lb·ft (400 Nm) engine.
2004-2005 models came with a 6-speed manual transmission, as well as a 5-speed automatic which allowed only 258 ft-lb. torque. 2006-2007 models were available with a 6-speed manual or automatic transmission. The 2006-2007 Automatic Transmission allowed for the full torque of 295lbs. (however, this torque was still limited to 258 ft-lbs. in 1st and 2nd gear).
Other aspects which drew the R apart from standard S60's were the four piston brakes (BREMBO) front and rear, optional 18" 5 spoke "Pegasus" wheels, blue faced "R" gauges, standard HID headlights, as well as the 4C suspension system. (4C stands for "continuously controlled chassis concept") The 4C feature allowed the user to select from three modes; Comfort, Sport, and Advanced. This tightened the suspension progressively, and also made for enhanced throttle response when in "Advanced" mode. This is easily accomplished due to the fact the throttle is drive by wire, meaning the throttle is connected to the accelerator pedal via electronics instead of a traditional cable design. This allows for different throttle maps to be in place, which can be electronically altered to give a different feel when the accelerator is depressed. The S60 R continued the tradition of "R" cars for Volvo beginning in 1995 with the introduction of the 850 T-5 R.
Thanks to Wikipedia for contributing to this FAQ!