60% full means that about 87 people (144 is a full class) have comited to attending USC. USC has probably sent out more acceptances and still waiting for the answer from those people. also a bunch of people who have interviewd are still being reviewed... AS I remember, and correct me I'm wrong, the last few inteviews take place at the end of march for USC and extra round is usually also done if needed around mid to late April
good luck to everyone, hope to see you here next year!!
-Sean-