Text from the invite is below:
Dear Applicationist,I guess they aren't nearly as excited as I am.
You have been invited to interview for the MBA program at The Wharton School. To schedule your interview, which must be confirmed by 11:59 p.m. on Sunday, February 26, 2012, log into your Wharton account and select "Search" in the Events box to the right on the main page.
I'll let you know how my Booth interview goes this weekend.