I've mentioned before that my typical training shoe is the Asics Gel Enduro. As a reminder, this is billed as a trail running shoe, although 95% of my runs are on asphalt/concrete. These fellas weigh in at a fairly standard weight of 11 oz. They fir me snugly and provide what I consider to be excellent support for my foot. Aside from some minimal ITB I had after running two marathons three weeks apart, (Jax and Disney) I've not had the first injury (famous last words).
Anyway, one day I was kicking around on Zappos (the greatest internet shoe site ever) and came across some lighter racing shoes. I had been doing some reading about 'racing flats' and thought they might work well for me. The wisdom I had read was that they offered the opportunity for strong runners with good form to cut their time down by using lighter shoes with less cushioning and support. As an aside, this is also in fitting with part of the current iteration of the 'barefoot running' resurgence, which suggests that if you run with the right form, you don't need fancy overcushioned shoes, but that's a post for another day.
The lightweight shoes I settled on were the Fastwitch 3 by Saucony. Even better was the fact that they came in a great orange and blue palette (the current model is an equally obnoxious Lance Armstrong-esque yellow and black). These shoes cut the weight down to 8 oz. by removing as much material as possible. As a result, watch out for puddles, there is a hole in the midfoot to eliminate another 0.001 oz of rubber.
Again, very comfortable on my foot. The upper is basically all mesh with just a little rubber for support and the resulting feel is almost like snug slippers rather than shoes. They make me feel much faster when I run, but the best part is that I actually do seem to drop a solid :15 off my mile pace!
Now, I'm a doctor. I am keenly aware of the placebo effect and for all I know, the improvement in time is a figment of my desire to believe I am faster in my 'magic shoes'. Furthermore, I have only really run in them just prior to and during races. It is certainly possible that as nervous energy builds during taper and prior to my race, the excitement turns into adrenaline, which fuels my speed.
Of course, do I really care if it's psychological or physiological? I would be wearing shoes either way, and the cost difference between the shoes is not that much ($20)
I have enjoyed my Saucony's and if you feel up to it, I think flats might be worth trying for many racers. If I can drop my pace by 15 seconds, maybe you don't have to be Kenyan to enjoy a shoe specific for racing.