I have to agree with Hyori Lee on one thing. Prejudice is a big part of it.
The stereotypical asian asexual nerd is so prevalent that its hard to break out of that mold. The asian guy has to be pretty white washed for him to go toe-to-toe with the typical white guy pulling white chicks.
However, this doesn't mean a loss of cultural identity. One of the senior members in my fraternity is this guy from Hong Kong. Wears abercrombie, dresses hella white, chugs beers like any football player, and still speaks fluent chinese. Pulls white chicks, almost exclusively in fact, like you wouldn't believe.
The solution is to disregard race altogether, because it just limits you. I'm black (uh oh, here comes the azn vs black flames, I'm sorry for opening pandora's box), and I think asian girls are really attractive. However, there's usually a big divide between asians and blacks in general, regardless of gender. At first, I always used the race issue to find a reason to not approach, or to be generally uncomfortable, but as I dealt with asian chicks more, I learned to treat them like any other woman. They really aren't any different.
That isn't to say prejudice isn't there. Most asian guys are still put into the "nerd Starcraft player" category, but I don't think its fair to say that asian guys are genetically predisposed to not be able to pull white chicks, especially since there are short and skinny hispanic guys who pull hot white chicks like mad, short and skinny black guys (yes, those exist) that pull hot white chicks like mad, etc. I will admit though, many of them are pretty white-washed.