I went through a phase about a year ago where I removed the clips from my pedals and just rode on plain, flat platforms for a while, swearing I'd never go back. Riding "au natural" was such a no-brainer when it came to all the traffic lights and STOP signs along my commute.
But ultimately, I began to long for my clips again, and now they're back. I would never ride any kind of pedal where half of it sticks to my shoe, or where I have to buy and lug around a special set of shoes just to get from Point A to Point B.
I'm with the crowd that suggests either clipless or nuthin' at all!