The 2002 was the 1st gen SV650, and the 2007 is known as the 2nd gen. The 2002 model does not have fuel injection whereas the 2007 model will have fuel injection. The 2007 will start much better in the cold because of the fuel injection. The 2007 also makes slightly more power and torque than the 02.
The 07 has a digital speedometer, a digital clock, and a water temp guage, the 02 has none of those. The 2007 has slightly better tuned suspension, and offers a bit more adjustability then the 02. The 2007 has an oil cooler, and the 2002 does not.
Here is a bit more information on the differences between the two.
http://forum.svrider.com/showthread.php?t=40032
