During interview day, I think the admissions rep said approximately a third of students are invited to apply for the Dean's scholarship. I wouldn't be surprised if everyone who applies gets a little bit of money. I believe Case is aware of how expensive their tuition is, and they do want to make it slightly more affordable for people and incentivize prospective students to attend Case over other cheaper schools--even if it's only $10k-$15k per year. It keeps down the average indebtedness of their graduates (as does need-based aid).
So approximately a month ago (mid-January) when I got my acceptance, I joined the incoming class Facebook group and there were ~300 members. Assuming they continue interviewing until March or so, I wouldn't be surprised if they accept 400+ people for a final class size of 180. Another user pointed out they heard the Dean say they were expecting better yield from accepted applicants this year because of the new building, but I don't know if that will be as huge a factor as they think. The HEC building isn't even finished yet--if a tour had been possible during interview day, I can imagine it being a factor, but until you see it in person I don't believe it will be as important a factor as location/prestige/cost.