Bike choice for snow commuting
I've got about 20,000 miles experience commuting in Alaska snow.  There are really 3 kinds of snow to deal with:  deep &amp; fluffy, hard &amp; icy, and slush.

I have two bikes, a Pugsley with Large Marge tires for deep snow, and a Kona 29er for everything else.

The trick to the Pugs is deflating the tires so they track right.  10psi in front is maybe too much, add a little more for the back. That makes a slow commute.  When the snow gets over 2-3" of thick stuff the Pugs comes out.

Otherwise it's the Kona with Nokian Gazza Extreme studs. Pump them up hard and they cut through to the hard surface under the goo.  Ice is no biggie, it's like riding on gravel.  The springtime deep slush will shoot out through the open deep tread pattern and you can pretty much just ride straight through it without tire deflection.  I recommend studs on your boots for ice riding too, when you put your foot down you'll need the traction at intersections.

Flat studded pedals, disc brakes, GOOD bright flashers, and you're set.  Saran wrap taped over your helmet vents keeps your head a little warmer too.

Try a camping headlight under your helmet.  Look at drivers at intersections and they see your beam, and see you.

Enjoy!