So, let's get a little bit more scientific in our investigation.
It all began 4 days ago. After the GOWIII GTTV episode, I guy named  Matthew Diment tweeted this:
 
To that, Geoff replied as follows
                    
 
From the above, we can state the following as facts:
FACT 1
- It's a 1st party title (Matthew mentions "Sony's first party  developers" and Geoff says "they")
FACT 2
- It's technically OMG material (Matthew goshes over GOWIII graphics and  Geoff hints at something as least as impressive by saying "wait until  you see")
So, a day ago, Geoff pimps the next episode of GTTV by stating the  following:
                    
 
Here are two more facts
FACT 1
- It's a surprise, meaning it's an unannounced title. 
FACT 2
- It's a sequel, meaning... well, not a new IP.
Let's put this facts all together and we get this:
It's an unexpected sequel to a Sony IP developed by a 1st party team  which shows some pretty amazing graphics.
Edit - 
Extra Fact: it's not Resistance 3 (confirmed by  developers)
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