The truth is out there ... and not hard to find at all:
http://www.ati.com/products/radeon96...o/compare.html
9600SE and plain 9600 use the same core and RAM, the SE just has half as many RAM chips and a smaller, low profile board. Some don't have the 2nd VGA output either.
9600XT comes from a chip manufacturing improvement - hence the much higher core clock - and is supposed to replace the "pro" flavor. "Pro" cards have a pre-improvement chip that won't clock nearly as high.