Re: 748 model year differences? (superbike2001)
The most notable differences are going to be aesthetic, i.e. differences in frame color, wheel color, wheel supplier, graphics. Really pretty minimal differences between the 748 lot. Someone who knows more about the rocker issue might be able to chime in here and tell you which years to avoid as ducati had some lackluster chrome contractors on a few of the years (either '97-'98 or '97-'99 IIRC). Two different front brake caliper spacings through the years, as on the 9XX's. 2002 had a different midpipe setup as well.
I can name off the aesthetic differences like I was talking about above but I doubt that's really what you're looking for when it comes to real differences, which there aren't many of.