With USB cables, as with other cables, the "cable controversy" is ongoing, eg:
http://forum.audiogon.com/cgi-bin/fr.pl?ddgtl&1259463304&openfrom&1&4#1
http://forum.audiogon.com/cgi-bin/fr.pl?ddgtl&1259463304&openfrom&1&4#1
high end USB cables - A to A connectors