Yes, Tito, OEMs use CoreSingleLanguage SKU for deploying, but I'm pretty sure it's true that you can do it on Core(Not Single Language and Win8 For China, just Core). I'm currently working in OEM so I've made several attempts on this...and I've posted the screenshot on another thread to show that clean core install can be successfully activated.
I installed CORE off a MSDN downloaded DVD on my Toshiba Notebook as a clean install to get rid of the Toshiba bloat, it came with core preloaded. I didn't need to enter a key during the install or anything, and once I was in Windows I noticed it was activated as soon as I checked.