If amd releases 8c excavator Intel just releases 8c broadwell or 12c if that is needed. Thats what is preventing amd from doing it. No matter how fast exc is Intel holds a significant node advantage. Broadwell is probably far slimmer than exc as exc looks quite beefed up.
But it would be great if 8c exv is released. It would mean an overnight doubling of cores for us desktop consumers. At the same price.
Intel E models have a gigantic markup even for Intel standards. I have absolutely no problem imagining 8c Intel q1 2015 and excav 8c at same time for 200-400usd. Intels solution far, far better efficiency and a little bit faster and cheaper to produce. I dont really think the market is important in any way. Haswell desktops is just an oc mobile processor with a different name. But it would be great for us desktop nerds 😉