One of my favorite books is Snowcrash by Neal Stephenson. It's a fabulous read. The main character is bi-racial (black and Korean by way of Japan(if I recall correctly)). A group of my friends and I were discussing the book when one of my friends said that they had issues with the main character because he was such a "weeabo." Now, to save you a trip to Urban Dictionary, a "weeabo" is someone that is unhealthily obsessed with and woefully misinformed about Japanese culture to the exclusion of their own. It's a term I don't like to use(hence the quotation marks).
But I digress. I thought the interpretation was very strange and it got me to thinking about why they would feel that way. I don't think that the confusion was with the character development; it's pretty straight forward and integral to the story.
Which left it as a reader interpretation issue. That's not a dig. It's just something to think about. Our programming automatically goes to what is familiar to us. Readers immerse themselves into the story, and thus, will take on what the reader knows. That includes race and ethnicity.
Not that that's a bad thing. Unless, of course, it's vitally important that certain characters identify as another box on the census. :)
But then you run the risk of of writing from a perspective about which you have no clue, or accidentally offending an entire segment of the world's population. It's enough to drive you mad.