In the new Game Informer magazine there is something that says this game is running on a new engine called Fossil Engine.
If true this is good news. The series was in need of a new engine. Saying that we were told Ghosts ran on a new engine and then later told is wasn't actually a new engine but just the old one heavily modified. So we'll have to see.
Also, a fossil is something that is ancient. So....
I get this feeling that it is still a heavily modified IW engine. If I was to make a comparison to a previous COD title, it reminds of Black Ops II but the textures are heavily detailed and visually better. However it could just be the futuristic setting fooling me.
But don't get me wrong, Advanced Warfare still looks stunning from what we've seen so far. I mean COD Ghosts didn't impress me visually for a next-gen release but I'm forgving IW considering that their time given on the development on Ghosts was much shorter than what SH Games and Treyarch have for Advanced Warfare and COD 2015.
But if this new engine is true, I'm glad. As you said, hopefully SH Games have also worked out the kinks on connectivity and matchmaking that has plagued COD for a while.
Every Call of Duty has a ran a new engine. Maybe not a brand new engine from scratch but each year we have arguments over why that's impossible to do. This year we get a brand new shiny engine built from the ground up. In past years Activision invest money into taking an old engine (which is use solely for graphics and game mechanics, not networking) and strips to it's bones and renovates it. Building a new engine each year is impossible because of the massive amount of time, effort, and money a company would need to invest.
Completely based on ancient memory, but I believe I read an article a few years ago where a developer spent 200 million on a new gaming engine and it's not like that gaming engine was super insanely popular.