You can't say that AMD hasn't got little media attention the past few months. A set of slides surfaced at the usual suspect, this round a set with VEGA 10 and VEGA 20 slides.

These slides (which are not new btw) give some more insight on VEGA,. The VEGA information from then compared to now does seem to match up fairly closely. I do have to state though that the slides still do look slightly very odd, the logos used are dated and they do not match up with what is the style that AMD uses in their slides. Also the Radeon card pasted into the slides simply seems like a photoshop hack job ? Who knows though.
  

 
In the first slide you'll see that Vega 10 gets 64 NCU or Next-Gen Compute Units as AMD (x64 = 4096 shader processors). TDP is set at 225 W. The HBM2 memory comes in at 2 stacks at 16GB for a total of 521 GB/s, this value is off as we think it should be 8GB. Then again it might be a different SKU. Performance is rated at 12 TFLOPS for single precision and 750 GFLOPS for double precision. Also spot Vega 10 x2 which seems to be a dual chip solution coming in at 300W with likely lower clocks.
  

 
Vega 20 is mentioned in the enxt slide to be released second half of 2018. It is mentioned to get the same 64CUs as in Vega 10 and is fabbed at 7nm and features PCIe 4.0. TDP  has a wide range of 150W to 300W, with I presume several products all at different core configurations and clocks using the same base die. 
  

 
The last slide shows a server road-map for future products and mentions architecture codenames. As with previously released slides, Navi 10 will arrive in 2019. 

Again here I have to say, the slides still look like a hackjob, but the Vega info does have some merit on them.

AMD Vega 10 and Vega 20 Slides Revisited