I suppose "dawg" is an accepted GANGSTER slang meaning no more harm than Dude....
But in a multi-cultural environment, avoiding these slang titles are much more diplomatic, since they are not known in ALL the cultures, nor are they accepted in all the cultures.... I think in most places calling someone Dawg, is viewed in the same light as calling a female a b|tch. Its considered a degrading way of addressing someone.
I am assuming you didnt mean the degrading form, but now you know that it is widely viewed as very degrading.
All of us chose our nicknames in a way that the abbreviated form can be used as either our name, or title...