Coreboot is a good thing, but it's going to be hard to succeed without hardware vendor support, and that will be hard to build unless people actually want the product.
I work for a VAR. Our preferred vendor was one of the first to market with motherboards that expressly supported Coreboot. We're supporters of OSS, and so are our customers, so we figured that they'd be popular.
We sold only a handful over about two years. Our competitors didn't seem to have much more success, as our vendor didn't continue the experiment into the following motherboard generations.