My truck, a 97, threw the same code, so I took it to autozone and they told me the same thing you said. But after seeing the prices for replacing the sensor I decided to take it to my local stealer to have them read it (only $30) I figured if the part was going to cost that much, might as well spend a little more to be sure. Not to mention mine would only throw the code every now and then. Like ever couple weeks and if the sensor was bad, then it should throw it right away.At anyrate, the dealer told me that my two o2 sensors were mimecing one another, and that ment my catalytic converter was going bad. Which was even more costly to repair. So I haven't fixed mine yet, the light comes one once ever 2 or 3 weeks. I figure it can't be completely bad yet since I drive it everyday. Just thought I'd give you my .02.

Chris