I would recommend getting your form down perfect. Because it's so repetitive, running is tailor-made to produce long-term, slow-to-appear, tough-to-diagnose pain and injury. Incorrect form might be fine for now, but over time it could cause trouble.
(I can't vouch for these sources.)
If your feet turn out to the side as you run, it torques your knee with every foot strike. Your leg isn’t designed to work this way. This action overworks the ligaments and tendons in the knee and eventually leads to pain. He says that the key to fixing this problem is to imagine you’re running on a tightrope, with your feet hitting along a line stretched out on the road directly in front of you.
This guy on a running forum points out that foot turn-out is not just inefficient--it caused him groin pain. It's of course anecdotal and a prime suspect for the placebo effect, but his solution worked:
So was it hard to fix this, you ask? No, not at all. I just remained conscious of it today and didn't allow it to turn. When I ran fast or went up hills, I made sure to keep my toe pointing straight ahead and sure enough, no more groin pain. So during my entire run, I felt great and fresh. I was always accelerating and never had one of those moments where I'm shuffling about. My stride remained long and relaxed.
Trainer Blake Robinson says to check for glute tightness:
[I]f your Gluteus Maximus is too tight your feet will turn out to the side as you run causing you to run on the outside of your shoe, also known as duck feet, which in turn increases the strain on the inside of your knees. To check how far your feet turn out as you run find a treadmill that faces a mirror and watch your feet just as the push-off and leave the ground.
It's possible that your gait is fine, but it definitely can't hurt to do some diagnostics. I would find a subject matter expert (i.e., a personal trainer who specializes in runners and whose trainees you want to emulate) and take a session with him or her.