I don't think I'd get too cheerful just yet. His election does signify that a majority of Americans (a fairly large majority) were able to look past his race. That's about it though. That minority might still have a lot of power for actions that affect them in their everyday lives. Some have also been arguing that he wasn't black enough (I thought I heard Jesse Jackson getting some people riled up over it). A dumb argument, but it shows that there will always be some tension.
Either way, it is a good sign of how far we've come.