While some sites proclaim this is evidence that the launch of the 300 series is imminent, we're skeptical as during the earnings call just two weeks ago AMD's top executives revealed they expect to regain marketshare with new GPUs and APUs starting in the second quarter of 2015.
As such a launch of the R9 300 series is unlikely in the coming weeks. Maybe they'll be able to squeeze it into March but it's more likely going to be April at the earliest, if not a launch at Computex in June.
The Facebook post officially confirms the next-gen cards will use Radeon R9 300 series branding though, but other than that there's still very little credible information about the exact specifications of these cards.
The new High Bandwidth Memory (HBM) is expected to make a big splash but we still don't even know if the flagship model of this generation will be the Radeon R9 380X or Radeon R9 390X. Some benchmarks have leaked recently but we haven't posted these as they are most certainly fake.