I am, as I type this, wearing my Decente Element gloves (mine are last year's model). -20ºC (-4ºF) today, and I wore them to work, no problem. My building heat is still having issues, so I've been wearing them off and on at my desk. They're agile enough that I can slowly finger-type with them on. I think if my ride was more than 20-25 minutes, I might want something thicker, but for my purposes, they work great. My finger do sometimes feel cold - the lobster version might be better for this - but they're good enough that's just a slight discomfort. Not anywhere remotely close to a frostbite risk.

They've even got a nice bit of terry-cloth for wiping my snot. How thoughtful is that.