I'm one of the "bike only" crowd but if I really need to I can grab the wife's car. Not that easy though since she's a stay-at-home-mom with our little dude. Then again my commute is 3 miles in Austin...
One little thing you may consider, and hopefully it doesn't kick off a flame war. Don't spend extra for a SNELL helmet like I did. I honestly think they may be TOO stiff for around town speeds. Got a buddy with a severe brain injury right now because somebody pulled out in front of him at ~ 45 mph. His helmet is barely damaged (at least visibly... I know the foam may be compressed, etc). Based on my helmet (bicycle and motorcycle) usage over the years, you want something that is going to soak that up, not just bounce off...
And please man, be cool with the cycle. They are sooo much fun... but I want to hear about you riding with your buddies in 20 years, not sitting in a box in the ground (or worse). Sorry for the weird downer, but I'm still a little freaked about my buddy mentioned above.