@whiteagle: wow, that doesn't even seem that bad. Did she get 2 B's and all the rest A's and are you referring to first or second semester? The reason I ask is my friend got in to Columbia ED and got 2 B's first semester and 2 B's and a C second semester and nothing happened.
Also, to the OP, I believe a good rule is just don't get anything lower then a B and try to avoid keep a B+ average, however, according to whiteagle, they may be stricter, but thats just what I have heard. Basically, just don't slack off.