Those seem kind of redundant with the added compute efficiency of the PS4 GPU. Maybe they were in dev kits to simulate the physics processing abilities of the final unit but they just seem like they'd add to board complexity for little benefit.
maybe it's better at some task than the GPU at computing & if I'm reading it right it seem like Eurogamer is saying that you can use the GPU for extra compute power & use the GPU like chip for extra graphic power. so it seem like it will be just like the SPE's & it would have to be pretty powerful for them to say something like use the GPU for compute & use the chip for extra graphics.
PS2 had 2 Vectors Units about 3GFLOPS each
PS3 had 7 Vector Units (SPE's) but only 6 usable for games 25.6 GFLOPS each 179.2GFLOPS
now PS4 is rumored to have 8 but the specs are unknown but if we go by the jump from PS2 to PS3 the Vector units would be 8X more powerful.
so 8 X 25.6 = 204.8 GFLOPS each
& it's 8 of them so it would be 1.638TFLOPS add that to the 1.84TFLOPS GPU & 104GFLOPS CPU & you have a 3.58TFLOPS Console which is closer to 10X as power as the PS3
I know I look crazy for even thinking this but it's the same way all the other PlayStations have been.
(waits to be disappointed with the real specs of the chip)