I don't but I love them. There are so many paint effects for concrete.

I did years back and I don't like how hard they are on my feet and back. I don't like tile either for the same reason, but at least tile is set on a subfloor with a little "give" to it. Concrete is, well, concrete. They also require sealing on a regular basis because they get wear areas around the sink and traffic areas. Fine if you like that kind of look.

I'll agree it would be hard on the feet

Anti-fatigue mats at the main workstation/standing areas (sink,cooktop,etc) will take care of the hard-on-your-feet issue. Personally, I can't feel the difference between "non-resilient" and "resilient" flooring - it's all uncomfortable - so I went with mats and ceramic tile. Concrete is a really nifty material; if my kitchen was slab on grade I would have seriously considered using it.

I'd recommend having in-floor radiant heating installed when the slab is poured, if possible - it's cheap to put PEX in during construction, not too expensive to put electric heat cable in, but impossible to add later. You can always put the pipe/cable in and only hook it up later if you decide you want heat - but concrete does tend to get cold easily, just like tile or stone.

LUV concrete- we are currently building our countertops and then plan to do fireplace hearth and concrete floor for our entrance foyer. The floor will have an integral pigment and then sealed. For floor sealer check out Pentrasil 244+ at Convergent Concrete - no resealing and tough. i have been documenting our progress at the Ikeafans site if you are interested - search "bought the cement mixer". I'll warn you though that it's alot of work but well worth it if you like the look and enjoy doing it yourself.

I currently have a concrete kitchen floor--the slab. We're in the deconstruction phase.

I had considered porcelain tile but living with just the bare concrete these past 2 months taught me something--it hurts! My feet, legs, hips and back ache when I'm in the kitchen too long. Granted, I'm usually barefoot.

My grandson has taken a few falls on it (because he's 21 months old). The sound was sickening and he really hurt himself each time.

If I were you, I'd try walking and standing on cement before seriously considering it for your kitchen. It's personal preference, but I'll be going with hardwood.

It's true about the possibilities for paint on the concrete, but for a kitchen, get it colored in the mix (integral pigment per Biner above). I had gorgeous painted concrete years back and it was a real pain to clean. The paint (sealer?) seems to grip spots and dirt and there's a lot more hand cleaning than other surfaces.

'Course in my kitchen it doesn't matter what I get because there's concrete underneath :)