You're right Becca, it just depends on the rabbit. Midnight, my brother's rabbit, literally hates everyone but him, and Midnight's momma Ivory* was the same way. I think 9 times out of 10 their moods are just hereditary.
* Yes, you can get different colors in the American breed even when bred pure. Midnight, an American Black, was the daughter of an American White mom and an American White dad and sister to 4 Black and two Blue siblings. Just because they are pure bred Americans doesn't mean they won't throw 1, 2, or even all 3 colors into the litter, which is 1 of the many reasons why I love Americans. And yes you can breed the different colors together, because they are still the same breed. In other breeds, if you mix color, you usually end up with splotched babies. But with Americans, it's rare to have babies that are NOT solid colored. I personally love the Blues the best.