I can understand rinsing a glass to ensure that there's no soapy residue to throw off the flavor of the wine, or other beverage. When I used to judge beer competitions, we would prime the glass with water or a very light beer to get rid of any soap, since soap would take away a beer's foamy head.
As for wine itself, I would suggest rinsing, or seasoning, your glass with the wine you will be drinking, not a "pace car" wine that has a different flavor profile than what you will be tasting.
- Mark
Homer: Are you saying you're never going to eat any animal again? What about bacon? Ham? Pork chops?
Lisa: Dad, those all come from the same animal.
Homer: Heh heh heh. Ooh, yeah, right, Lisa. A wonderful, magical animal.