This is your chance to show how much you know about this school, and how well you fit. A detailed and thoughtful response demonstrates you cared enough to research the department of your choice in advance. If you’re super stoked on the school, by all means, express it, but stop short of sucking up. And if you’re not that stoked on the school, but it’s your only option for financial or convenience reasons, you better think of a reason to get excited about it – fast.