2-3 years tops on lifespan with high usage for a TV that costs a hell of a lot of money at this point in time. And you are correct, the blue spectrum has proven to be the first to go, so it will render all the images out of whack once this starts to happen. Plus, since they don't require multiple layers of filtering, this is why the panel is so thin - even that is at the expense of overall sturdiness - very fragile.
The technology is very interesting, but I think I'll watch it from a distance for quite a while until it comes around to being a viable consumer product.