Bond has his martinis 'shaken not stirred' because he had them with vodka, not gin. You never shake the gin because it might bruise the gin. In cocktail land, its called a Bradford. Interesting to note, that the "shaken not stirred" from Bond is a reverse of the books, where he (of course) in classic fashion, wanted them "stirred not shaken." Though in the books Bond drinks pretty much everything.