Everyone seems to think that the people that ride fixed gears use straps, and maybe some do, but pretty much everyone I have ridden with uses SPD clipless or CrankBrothers. A few guys use the straps. I usually laugh as they are struggling to get their non dominant foot back in the strap after it has flipped over several times.

I started with SPD's on a mountain bike and made myself learn how to use them. Now it is second nature and I have them on all of my bikes, from a fixed gear track bike to a carbon road bike to my cx bike.