The Pottery Barn - Closed
Victoria Secret - Closing on Michigan Avenue and Chicago when they re-open where Pottery Barn used to be (supposedly summer '09)
Borders - Closing by Jan 2010 (wonder what they are going to do with that space since only Filene's will be left. YIKES!)
The Disney Store - Closing by Jan 2010
Ethels Chocolate - (In the Nordstrom mall... all Chicagoland Ethel's are closing)
***UPDATE*** Can't believe I forgot this one, but Starbucks between Erie and Huron also closed late last year. This is not due to the economy, but to the new condos that are being built. The condo association/builder/whomever didn't want any outside businesses in their complex. This is stupid as hell from a business standpoint if you ask me, but hey, maybe they know something I don't.
Damn economy... Michigan Avenue's about to start looking broke down like State Street. Womp.