I've had a handful of arguments w/ smart people about Mary's room lately.

The conclusion I've come to is that the disagreement typically rests on how you define "knowledge." To many, "what the color blue looks like" does not constitute knowledge, because it doesn't enable you to make any additional quantitative statements beyond what you would know from an objective study of color/light. But in common usage, we say things like "I know what that feels like," meaning "I've felt that before." In the end, this is just a semantic disagreement.

But there are still philosophers like Dennett who take an even harder position, saying that functional knowledge is identical to experiential knowledge. I still can't quite wrap my head around this idea.