Here is the relevant blog post. Long story short: Paradox Interactive (ha) purchased White Wolf from CCP. They have decided to re-brand things a bit under their idea of "One World of Darkness." Thus, the 4th Editions and 20th Anniversary Editions and so on will be the World of Darkness, while the no-longer-new-World-of-Darkness is now called "Chronicles of Darkness." This ultimately is meant to avoid confusion and perceived inter-company competition. Production is, as far as I know, going to remain unchanged save for the names, but at some point it might be prudent to update the system to reflect the name change.
