There was recently an interview with a AMD rep and two question were interesting for us regarding next-gen console. It looks like ps5 and Next Xbox will have a chiplet design instead of a SOC/APU.
Basically what this means is that Sony and Microsoft can pump in more Gpu cores into their next console. Something like a 88CU clocked at 1400mhz giving 15,7 Teraflops seems very feasible. Probably Vivster or Pemalite can give a better explanation what chiplet design is.
While that sounds like a good idea at first, it really isn't practical for something like a console which has to be cheap to manufacture. Chiplet designs require much more time to design, it requires interfaces between the chiplets (and this at very high speeds) more testing individual components, and some other, more obscure things. In the end, the price will be too high so I expect a monolithic chip, again. One chip still is the most cost effective solution for products that have to be cheap to manufacture.