Jane Aquino over at Raindance makes a good point – an arrow in the actor’s quiver (ha ha! bonus points for the double meaning) should be the ability to convincingly do a different accent. In these top 10 examples Jane showcases some good inspiration material. After all, if Tom Cruise can do a convincing (jury is out here) accent then surely you can too!
As an aside, my Japanese is not good enough to discern this but I am told the same thing exists here – actors doing region dialect and accent. So, if it is true in English and true in Japanese I will extrapolate that it is true the world over. Actors – learn your accents!