I commute all winter long and have never been tempted to get studded tires. My experience with them on cars showed me their best value was when powering through a slick spot --essentially carving deeply into the ice to get traction. I can't (don't want to) do that on a bike. I'm not convinced studs would be any better on ice, AND 99.9% of the time I'm not actually on glare ice or can totally avoid those patches. (I can't believe I'm going to say this)--I have never fallen on ice yet. I am careful to stay in balance on top of the bike (no leaning) when on slippery patches.
Edit: But now that I think of it.. in rutted ice it might be very useful to have side studs at least.
Last edited by dbg; 01-23-13 at 11:00 AM.