it gets cold here, especially in the mornings. It was 33 this morning, not too bad. I ride unless it gets close to 0, and then I take the car. I know, it's only Oklahoma, but it does get that cold occasionally. Usually it's in the high 20's or low 30's from November to the end of February or so.
I have to wear slacks ( thin) and a dress shirt ( also thin) to work every day, but I really don't do much for the ride - thinly lined gloves bought on clearance at CycleWorld, cheap dollar store thermal underwear under the slacks, a leather jacket ( I don't even bother with the liner anymore) from LeatherUp purchased for 59 bucks, a balaclava for my neck and face, and an open face 3/4 helmet with a 7 dollar 3 snap plastic shield.
It just doesn't bother me that much, really. I've gone the "seriously bundled up" route, and this particular combo keeps me just as warm with less bulk.