If you are a commuter, the best strategy is to stick to the dry and salted roads. You'll probably want to slightly lower your tire pressure, and possibly your saddle -- because you can be sure that at some point in the near future, your tires will lose grip around a corner and you will need to put your inside foot down to prevent crashing.
Recreational riders and racers will want to either switch to their winter bikes, or at least consider swapping tires and/or wheels. And while cyclocross bikes are obviously preferable in these conditions, properly adjusted road bikes can be used all winter long. When there is a little snow on the ground, even skinny road tires can maintain grip on dirt and grass. In the photo above, some Tatitos are preparing for a snow criterium. I think the riders on cross bikes might have crashed more than the roadies!