> From my reading, four of the shader units in the PS4 are reserved for Compute Units; things like physics (just cause 2) and lighting (battlefield 3), which cuts the raw advantage from 50% to 16%. Apparently on the 720, developers will be able to choose how to allocate compute units across the cores.

You are reading bad sources. PS4 can allocate everything to graphics. And even if it couldn't, a lot of the graphics work in today's game engines is run as compute shaders anyway, so it would not matter in the slightest. The whole "cuts the raw advantage" spiel was concocted by fanboys to make themselves feel better. I strongly advocate that you pay no heed to anything said by anyone who mentions it.

> Mainly useful for stereoscopic images or 4k. How many people have 4k tvs and 3D tvs? 16 render output units are plenty for 1080p (the PS4 has 32).

Completely untrue. The load on rops doesn't depend on just resolution, but on what they draw. In deferred engines (which everyone uses now), you can often reduce load on other parts by storing intermediate results, spending more fillrate. On consoles, everyone designs their games to spend all the fillrate that is available.

Fillrate does, however scale linearly on resolution and frame rate, so if a game is designed to run on Xbox next at x resolution and y frame rate, to run at 2x or 2y you would need twice of it. Which is probably why Sony has exactly twice of it.

> At the cost of half the storage (4GB vs 8GB).

?!? What exactly are your sources anyway? PS4 has 8GB of GDDR5.

> Textures will probably be able to be larger on Durango

Umm, no. More memory means larger textures. The textures will be pretty much identical for the consoles.

> More of some things; less of others. Faster at some things; slower at others.

No, Orbis is strictly superior in everything. Which is my point.