Think three inexpensive SVGA front projectors... ;)
LCD's work pretty well, I find, but the fixed resolution problem is not going to go away, since panels have a fixed amount of pixels on them. They will always stink at any other resolutions than those, just like LCD front projectors.
The...
You could do it with 17-inchers too and get quite the experience... but the ultimate would be a set of three LCD screens, ones with very narrow borders.
The biggest question marks for me is driver quality, or "hassle level"... At least part of the reason Nvidia is king of the hill is that they have a great driver department. ATI is still playing catch-up and you have more problems getting things working... but the question is how Matrox will...