Might as well add a me too in here...
Tuesday was my first commute and went again
Thursday. Mine is about 20 miles round trip. I've been posting my experiences in the SE "did you ride today" thread. That's where I'm linking. My biggest challenge is the heat in the afternoon. Beating it pretty well so far! I figure if I can handle the worst of it through the summer, the rest of the year will be gravy.