I have not played the first to games so i will say this, Bethesda do not usually pre-decide your appearance, so this time around one could imprint the vision that the Dovakhiin on the screenshot behind these words "is" Dovakhiin. For me it kind of feels that way now, i will probably customize my character later but first if the option will be available, play as the 'standard'.
there has never been a "standard" in any TES game, even in Fallout 3 they've left trailer characters pretty vague compared to games like Mass Effect, where "THIS is Shepard but you can make your own if you really wanna".
The Nord male you see in the trailers is probably pure in-game face preset 1. though with that helmet its hard to make out much details at all. If you talking about Male Nord vs The other races/genders. I doubt anyones been too persuaded by it. Nords just fit better given the Zone but for all we know he could be an imperial or Breton given you really dont have anything to compare him to size wise in the trailers (race vs race)