08-05-10: Tvad
My experience has been that gauge matters more than materials, construction or brand. A larger gauge provides more richness. A smaller gauge provides more detail, and a more "open" sound.
But if you have a cable made up of several small gauge individually insulated conductors twisted or wrapped or woven together to create an aggregate large gauge (e.g. Kimber 8TC or 12TC) you get the best of both--richness and deep bass control as well as delicacy, air, and inner detail.
I'm currently running Zu Audio's 10-gauge Libtec cable and it definitely provides both in spades (or bananas, nyuk-nyuk).