The idea is that these two men each brought his own set of experiences to the interaction. For Dr. Gates it could be the story of what has happened to black men in confrontations with police in the past and his sense of his identity as a scholar and a man in his own house. For Sgt. Crowley the narrative has to do with the uncertainty and danger of what may confront a policeman in the situation of a possible break-in and his own vulnerability as a husband, father and cop. Both stories seem to involve fear of the Other. Both these narratives are emotionally loaded and when emotions take control, rational behavior disappears. I am oversimplifying this and cannot put it as eloquently as these writers did. Is racism involved? Probably, but just labeling it as such doesn't help us explore and learn what needs to be done. (Personally, I think Dr. Gates was unnecessarily handcuffed and arrested and justifiably angry.)
How can we use these powerful personal narratives ( back in the 60s we called it "where you're coming from") we all carry especially when they have an impact on race and other cultural differences? We are all so proud that we elected an African-American as president that we think we have the racial issues in this country signed, sealed and delivered - and we haven't. Maybe this incident will be a catalyst to do some significant and hard work, honest work.
By the way, I heard a conservative on the radio discussing this and he said he'd never heard of Henry Louis Gates. That's not hard to figure out: Gates is well-known outside academia to people who listen to NPR and PBS and read Harper's or The New Yorker, not media popular with conservatives.