Let me put it to you this way.
I have FWD and live North of Denver.
I go to the high country ski resorts almost every weekend in winter.
I lived through the snowiest winter in 25 years this year.
In 2 snow seasons, I have never been stuck or out of control.
The ABS brakes were used on ice this winter, helped me a lot, and should be the same on both FWD and AWD.

One drawback, and I DO NOT think AWD would help any:
You cannot use this car to pull out other cars stuck in the snow.
There is a load limiter ( stall monitor ) on the electrical system.
If you apply electrical current to the motor, and nothing turns within 1 second, all power is cut to prevent electrical overload / overheat. Thus, when tied to a tree stump or other car, you cannot move. You cannot "ramp up" the power if the wheels do not move within 1 second. And as you know, you cannot allow slack in the tie rope or chain and get moving first, because the "jerk" will snap the rope or chain. The gas engine has no power from a dead stop. The first few miles per hour are all electric. "Electric launch" is what Ford likes to call it. ( Of course I speak about a 2005, there could be "refinements" for 2008, but don't count on it. )

Once you are moving even 1 or 2 miles per hour you have tons of power.
99% of all people would do fine in a FWD.
Funny, 55% ( I think ) of all people buy AWD!

-John