I find I don't get nearly as cold running as I do cycling in a cold temp. My normal winter aerobic outfit down to about 30 F is tights of some sort (I really like the Hind Munich pants for running), a long sleeve wicking shirt, and maybe a vest. I usually start out with gloves and a little hat too but they end up coming off and going in the vest pocket.

Below 30 I switch to a light, breathable jacket with a T shirt under, LS thermal if it's below 20. And a little thicker tights. The gloves will stay on (they are thin) as will the hat.

Happy running! I too am quite enamored with it right now...to the point that I'd rather run than ride. Scary, but true. (But then, I was a runner before I was a cyclist and only quit running because I had to.) There are some really beautiful places to run in these parts. Looking forward to running the trails in the snow with my YakTracks!