Aero pedals with clips/straps. I have yet to give clipless a try, but I feel quite comfortable in clips/traps

Everything.

SPDs on the cross bike
Campy Pro-fit on road
Clips and straps on fixed gear/track/vintage road..with classic vittorias and slotted cleats or modified sneakers with shanks.
Platform pedals on porteur and polo bike with climbing approach shoes (stiff soles)...

everything, every pedal system has a place.

I have yet to try clipless, I use either Lyotard or MKS Sylvan touring pedals sans clips. I am a size 12 and the clips just don't work too well for me.

Heh, that makes me cringe every time. I feel like I'm fighting a one-man war for correct nomenclature. A platform is a specific type of toe-clippable designed specifically to only be used with toe clips. As you say, if they don't have toe clips, they're just 'flats.' Or plain pedals, or whatever.

Anyway, my preference depends upon what I'm doing. For fast or technical riding on my road or mountain bike (though I don't have an MTB at the moment), I prefer clipless pedals, by far. And among clipless pedals, I like road pedals a heck of a lot more than MTB pedals.

For anything else, I've found that I actually prefer to have flats on my bike, so that's what goes on my commuting/cruising around bike. I like being able to just hop on the bike without swapping shoes, to be able to just get off and walk around comfortably when I get where I'm going and without worrying about slipping around at the supermarket. I'm not a fan of clips and straps, though I rode with them for a couple years, and besides, I don't feel like I need any foot retention for sprinting between stop lights or cruising along a country road at 15mph. I LOVE my clipless pedals on my road bike, and I wouldn't dream of riding it with anything else, but I ride hard on that bike. I train and race hard, and really don't feel any motivation to ride hard when I'm on a bike that isn't intended for it. My around-town bike is for commuting, shopping and riding socially. It's funny, my friends who don't race will actually ride much faster than I will just getting around town. It's annoying as hell. Not a fan of getting tired and sweaty when we're out to hang out and drink beer.

I've been using clips and straps but recently got some Powergrips and really like them a lot. May switch all of my bikes over.

Don't buy the GR-9 and expect it to be anything like the Lyotard's. That was my hope and I really despise my set of MKS GR-9's

I just started using SPDs in my 89 Cannondale. I like them a lot--I'll phase in SPDs on a few road bikes and leave some with clips and straps. I have too many bikes to put SPDs on all of them. I like to ride platforms on my mountain bikes.

I'm a big fan of powergrips on my mtb, you can wear winter/summer/wet or any shoes you otherwise would need.My biggest reason is I have never had a problem with getting a foot out-RIGHT NOW,in technical areas with multiple sections to portage(clipless are too hard on my shoulders).It's easy to vary the strap tesion as well.Just riding them for a short time you can more or less vary the amount of tension on your shoe by turning them.A noob can just step them down to the peddle as well as not needing specific shoes .On a road bike there is no other option - SPDs. They are WOW.

If you can justify the $$$, these look pretty sweet (patterned after the venerable Lyotard #23 pedals):

How do you feel about the fact that so many parts -like these pedals- now are machined rather than stamped/pressed and assembled as before? I think i might like them better if they plated em with something shiny afterwards.