Pedals and Iliotibial Band Syndrome
I road my road bike with mtn bike shoes for a year before I bought a nice pair of triathlon shoes and I never had a problem. I just find that the mtn bike shoes weren't nearly as comfortable as what I have now.
I have struggled with IT probs since converting from marathons to tri's.
Your IT band should be relaxed during cycling. It should be all quads and VMO etc no IT band.
Look at your pedaling technique before shelling out big bucks on shoes and pedals. As you fatigue most people tend to let their legs rotate out (away from the frame) hence not pedaling in the straight up and down motion. Just look down and make sure your knees are in the same plane as the pedals. If in doubt go to a physio.
Speed Kills. Strength Punishes
It depends on where the pain is. The IT band goes from the outside of the knee (it starts parallel to the knee cap) and it goes up the outside of the leg up into the hip region. It never hurts to get it checked out though.
I had similar knee pain with my old mountain pedals and noticed that on longer road rides when my legs were more tired, my knees wobbled a bit more. My LBS suggested I switch to road pedals because they are designed to give you more long term stability for long road rides because they generally have a larger platform where as moutain pedals are made so that you have some give and movement for trail riding.
I use road pedals with mountain bike shoes - perhaps if you want to save a little money you'd be able to get the road pedals first and still use them with your mountain bike shoes????
My shoes look almost like road shoes though except that they have treads on the bottom which I like because they are much easier to walk in (and to run in during transition zones too). I also just found that they fit my feet better than the road version of the same shoe.
good luck!
I just finished a bunch of physio therapy for IT band stuff - nothing to do with my pedals and alot to do with stepping on a nail a while back and running anyways with a sore foot. My stride was just a little bit off and that much off multiplied for too many runs led to some IT band issues. Now if I could just solve the things wrong with my knees...............

Someone told me that riding a road bike with mtn bike shoes and pedals can cause stress to the Iliotibial Band. Now that my mileage is going up and I do feel a bit of pain on the left side of my left leg, do you think this is true and should I just get road shoes and pedals?
Thanks - Kristen