A good friend of ours has done many concrete countertops and they look amazing. We seriously considered it for our remodel. The staining/etching is what turned us off. To be perfectly frank I'm a slob in the kitchen. A countertop that would be damaged by red wine or lemon left on it overnight is just not feasible. Instead we went with soapstone. If it can hold up to legions of teenage chemistry students I feel it can hold up to me. :D If you do decide to go with concrete have you seen the books by Fu-Tung Cheng? They're excellent. Soapstone can be a lot more affordable as a DIY project. The quarry we bought from has DIY kits for about $25/sq ft or you could make it even cheaper by using tiles. Soapstone seams incredibly well.

just a follow up... the mortar bed was successfully removed. Turned out the easiest method was to ignore the tile top, other that to chip a few away to gain a visual of the wire sticking out at the edges. I found if I hammered at the tile top certain areas would come apart easily, these being the places where the wire mesh was connected. These areas were smooth metal, not mesh, so the mortar came away easily there. At these spots the mesh was nailed onto the wood board beneath. If I aimed my chisel between the wire mesh and the mortar it was relatively easy to separate it in sections. Once the nails were pulled out it was much easier to remove. Once it was all cleared away, all that was left was the wood board. The installer decided to use that board, since it was nice wood and provided a better surface with which to lay the new counter top onto than the "pieces" the counter company provided. Worked out great and the labor it took was worth the savings to us, as we got a price break for saving the installer time. sorry, snoon....can't make anything out of your comment, though definitely not helpful.

The "thinnest" workable height to add a layer of concrete would be around 1", and that's with using very small aggregate and fiber reinforcement instead of a traditional mix with a lot more strength. It wouldn't be thick enough or strong enough (even with the fiber reinforcing) to remain crack free, and it really doesn't have enough depth to be wire reinforced. And, you're raising your counters at least 1". Counters are 36" high for a reason. I'm sorry, but this sounds like another of those "HGTVisms" like glueing chicken feathers to a wall or using hollow core doors to make an outdoor table. It's "fine" for the 15 minutes it's being filmed, and a total disaster for someone to deal with after the camera stops.

I've had concrete counters for 20 years in two houses. Love them. I don't coat mine in plastic. I wax them. How much they stain depends on how diligently you care for them. I'm not diligent and mine do have all sorts of marks. I love it. It's like a patina and looks more like stone all the time with the years of use. Mine are "natural" with no colour added We poured them ourselves. No issues and cost under $150. Plan on same in next and forever house.