The weather has certainly taken a turn towards winter the last couple days. Very low temperatures mean ice is starting to form.
I would advise caution if you're planning on heading out in the local area though. The ice is still pretty sketchy by all reports. A few days and nights of this cold weather should get things started however.
For now, consider looking for panfish in protected areas with still green weeds. Crappies and bluegills will bite on a variety of small live bait or plastics around shallow weed clumps. The fish will not have set up their feeding schedule as of yet, but you can expect to catch fish in little spurts. If you have three holes going, chances are one hole will outproduce the rest. Spread out your gear until you connect, then fish hard through the most active holes.
Early ice walleye action can be great, but I'd give things another couple of days before heading out to exposed areas or flats adjacent to open water.