According to CoreLogic's March MarketPulse report (PDF), the Chicago-Joliet-Naperville CBSA saw 3,622 home sales in January of 2012, down 10.4% from the previous year. REO sales (1,267) and short sales (668) accounted for 53.4% of all January sales.
Mean days on market for active properties increased by 22.4%, while the mean days on market for sold properties decreased by 10.1%. The House Price Index fell 0.6% month-over-month and 8.5% year-over-year.
The percent of mortgage loans 90 days or more delinquent stood at 10.7% in January. Among homes with mortgages, 24.8% had negative equity. There was a 36.4 months' supply of distressed homes.
You'll find much more market data and analysis in the full report.