Similar situation here as the OP, only I actually haven't started commuting due to my only route choices between my home town and work town are 2-lane hilly roads with no shoulder, and most have considerable traffic doing 40-50 mph or faster. Or there's the interstate, which I'm pretty sure is prohibited to non-motorized vehicles, and I wouldn't want to venture there anyway.

Maybe one day I'll give it a try. Maybe one day when I have a faster bike and am better on the hills (am getting better little by little).