http://www.reddit.com/r/DotA2/comments/2cv5os/so_the_workshop_tools_isnt_just_a_modding/ So apparently the Alpha of the Dota 2 workshop tools was released last night and it runs completely on Source Engine 2. 64bit and DX11 support. Apparently they already ported the majority of their games over internally which they announced at dev days. Most people are reporting that it's still kind of buggy but if they are working it into the dev tools I'm sure the ports of all their games will be released by the end of this year.
My life wont be complete till I have HL2 DX11 fake factory mod in source 2 and HL1 remade in Source 2.