Can anyone give me a short run down of the benefits/drawbacks of installing hydronic heating in the ceiling vs. in the floor? I'm particularly interested in the actual heating performance and comfort considerations rather than "makes it easier to install flooring" type comments. :-) This is in new construction, not retrofit. I'm particularly thinking of ceiling installation because, from what I can find and read, using it for cooling will work better.

Consider using electric earth thermal storage system for your radiant heating below grade.  More efficient than hydronic and easier and cheaper to install.  Electric radiant ceiling system for the main and upper floors.  Check out the www.thermaray.com for more info.  I currently install and distribute these systems in SD and MN.  Works great in our part of the world.

No one has any experience or opinions to share? I'm surprised!

My Father in law was a plumber who built his own house in the 60s. He put radiant in the plaster ceiling (high temp boiler, copper pipe). The house was extremely comfortable. He did put the radiant in the tile floor in the bathrooms. My wife says she remembers how hot the small master bath floor was - probably because the floor area was so small and it was on an outside wall so needed high temp water for enough btus. She says with bare feet you had to stay on the small throw rug or you'd be hot footing it like a hot sand beach.

I think either system would work fine but your bare feet might prefer it in the floor on hard floor surfaces provided your btu requirement doesn't necessitate high temps.

Cooling with radiant is very tricky because of the condensation issues. It may be hard to find expertise in most areas. I hear it's used in Europe some.

There are a lot of factors that would depend on which way to go.  Building size, use type of flooring, amount of windows, passive solar design etc.  If you have a concrete floor, south facing windows and passive solar design, radiant ceiling panels are a great choice because the thermal mass of the floor with store the heat from the panels and the sun.  With infloor because you are heating the floor up directly and it will not be able to take as much heat from the sun or take too much.  This can cause a lot of overheating, even in the winter time.  Since the floor takes along time to react, in the morning you could be heating the floor and as the sun comes out the hydronic heating could be stopped but the sun will continue to heat the floor.  This actually happens in the winter at a library I know of.     
If your are building a commercial building,  there always seems to be a lot of tenant and wall changes, this can cause headaches with infloor when it comes to moving walls because of chances of puncturing a tube in the cement, also the zones layouts cannot be changed.  We have had many buildings with radiant ceiling panels installed and are very comfortable,  the key to preventing condensation when using them for cooling is to keep the chilled water temperature above the dew point.  Ceiling panels are more comfortable because it will either radiant to your head or your head to it, your head controls your comfort level.  Some critics say that you have to cover the entire ceiling with panels to get the proper coverage, this is only the case with a poor design.  If you get your solar heating loads down in the summer and get have high efficiency lighting and therefore need less cooling you can get away with less that 30% ceiling space coverage. 
Infloor seems good in areas without passive solar heat gains and high ceilings, that doesn't have a high cooling load.  People like radiant floor with because it's cozy on the feet,  but if this isn't a residential application you don't get near the same effect when you have shoes on.          
    

Thanks for the comments. I guess I should have said this is the ICF house I'm getting ready to build for myself. Floors will be 2/3 hardwood, 1//3 tile. All ceilings will be 9' except the living room which will be vaulted from 9' to about 13'. Attic and crawl space will be sealed and conditioned. The air here in SW Idaho is pretty dry so I don't expect condensation to be a problem given proper ventilation and controls. I'm also going to heat & cool the garage, also probably with in-ceiling tubing.

The ultimate would be radiant in the floor and ceiling both, but there is a limit to expenditures!

For some interesting info on ceiling radiant cooling go to BekaUSA.com and check out their slide shows. Also follow the link to the DOAS site, Dedicated Outdoor Air Supply. It's run by a Penn State Prof who, to put it mildly, vociferously argues the benefits of providing latent and sensible cooling with separate systems, doing sensible cooling with ceiling panels, and latent cooling by ventilation and supplemental a/c in the supply air as needed.

I have electric radiant on my basement floor and it is great. The warmth on the feet really makes a difference. Ceiling radiant gives the same effect?

Over an uninsulated basement floor, no.

In a suspended floor, well insulated, in a low load situation, yes, especially with wood/carpet floors.

Otherwise, floor is probably superior, but ceiling is better than convective methods typically.

My house will be 2 stories ICF with a walkout basement. I am leaning towards speedfloor/hambro for the first floor(all tiled) and TJIs for the second(mostly harwood/some carpet). I was wondering if 2 systems (hydronic radiant floors for the basement and 1st floor and electric radiant ceiling for the 2nd) can be combined effectively?

Why? You will already spent the money for your hydronic 'infrastructure', why deviate for one floor? You could go with Gypcrete(or various other above subfloor systems), or use 'staple-up'(which I don't really like).

Bottom Line: If you go with Hydronic I would use it for everything!!!