If you can commute, you should. The benefits are enormous, and there's really little downside.
I kind of fell into commuting. Our team ride leaves the shop at 6:15pm in September, and at 6:00pm in October. In order to make the ride, I began riding my bike to the office so I could go straight to the shop from work. This also meant I had to wear my kit. After a few weeks of doing this I realized, hey, this doesn't take any extra time than driving, and instead of sitting in a car I'm out on my bike! So I began doing it more regularly, and then started doing it everyday.
One thing I did incorrectly was gauging the effect of all these extra miles on my fatigue. I was still training hard at group and team rides during the week and on the weekend, and I was commuting at a tempo pace into order to get a workout in. And it was also increasing my time on the bike per week by about 5-8 hours.
So, I got pretty tired.
Eventually my body adapted to take on the extra mileage, and I also made sure to ride at a recovery pace more of the time while commuting. But I really went at it too hard to start.
Otherwise, treat it like you would any other ride - when you need to do intervals, do them, and vary your route so that you can have longer days, hillier days, etc.
With an infant at home, commuting has become a more crucial part of my routine, as well as early morning rides. I really think commuting can give a lot of racers who have limited training time substantial extra amounts of time.