Here is the info I've been able to gather on festivities -- actual Chicagoland residents can correct me if I'm wrong:
Saturday night ---
Bills party at Lincoln Station, 2432 N Lincoln Ave, Chicago, IL 60614
7pm-10pm. $30 all you can eat, looks incredible. RSVP strongly encouraged via Chicago Bills Backers by sending the names of you and your other party members to billsbackersofchicago AT gmail dot com.
There is also Bills-related drinking on Saturday night at the other Backers bar, Delilah's, conveniently located up the street from Lincoln Station. They are hosting a "Bills Backers Talkin Proud" party. Festivities begin at 6pm -- free wings and Genesee from 6pm-8pm.
Sunday morning ---
Red Pinto tailgate at a private lot south Soldier Field -- 31st St and Moe Drive, wedged between the train tracks and Lake Shore Drive. Lot opens early, don't forget the game itself is at 12pm Central for those traveling from the east!
Sunday gametime ---
For those without tickets to the game -- Bills fans will be gathering at Lincoln Station and Delilah's (2771 N Lincoln Ave, Chicago IL 60614). Recommend early arrival if you prefer to take your Bills games sitting down.
Sources:
http://www.bills4lif..._chicago_bears_
https://www.facebook...ackersOfChicago
https://www.facebook...backersdelilahs