I didn't mean for this to be a pro and con flip flop argument. Though I'm enjoying the thread.
My original assertion was that flip flops are not work appropriate in a professional setting, and look especially foolish when worn with business attire.
I myself proudly wear Tevas in the summertime, almost always with shorts and a t-shirt, but occasionally with jeans and a t-shirt.
Nothing against flip flops or sandals, just think they are completely inappropriate in a business or businss casual atmosphere.