Pretty much all the 390x rumors confirmed,
-4096 SP GCN 1.2, Double the performance/watt of GCN1.0 (Tahiti)
-HBM and GPU stacked on Single Interposer.
-Water Cooled Version is small form factor (no fans, very short)

FX CPUs:
-Up to 8 cores for consumer, 40% IPC over Excavator
-New cache system
-CPu and APU use the Same Socket (AM4)
-14nm FinFET
-AM4 to support DDR4, USB 3.1 Etc

(Excavator is about 5% higher than Piledriver, so about45% in IPC Alone Puts it around Haswell, then add in the SMT and Chache revamp, DDR4 etc, should be a nice lil chip)

Waiting for specs on AM4,

There are new AM3+ boards out with USB 3.1..