It all depends on your proportions. I'm 6'2", with 34" trouser inseam. My best-fitting bike is an old 59cm (c-c) trek. I'm currently looking at a 60cm (c-t) frame for a new bike, being the closest to the Trek in dimensions. I have a friend who's 6'6" tall, but has a similar trouser inseam, and he's happy with a 60cm Cannondale. Another friend is 6'2", but shorter in the legs, longer in the torso. He rides a 57cm Jamis, and he's quite comfortable.
In the past, I've found myself to be comfortable on a 61cm Bianchi, but not on the 59 (top tube is too shots). My fixed-gear is a 61 cm (I think), but with the short setm, it's fine.