Not necessarily. It's not like you receive half of white privileges and half the black stigma. You're seen as black, just that your black stigma is lessened. People may crack jokes about your half-n-half status (like calling you half 'n half) but overall it's better socially to have lighter skin than darker skin. This is especially true in the south where other black people are on that

crap and see themselves as better than darker blacks.
From what I've seen, if it is a girl, and she is pretty, than with the exception of black girls (since according to cac logic the only pretty black girls are the ones that have some other race mixed with them), they are seen as "white" or treated as "honorary whites", regardless of race. People may still crack racist jokes at them, and white guys may only see them as "fun" and not something serious, but most pretty girls seem to have all white friends.
Makes sense from their perspective. If you look like this, why hang with blacks when you're better off socially with cacs?
TvTropes even has an article about how people don't mind black people, but if they're too black
http://tvtropes.org/pmwiki/pmwiki.php/Main/ButNotTooBlack