As I wrote on the official forums I believe the lack of "dynamic cover system" as well as the very different graphics quality from the screens PC Gamer posted hint they are using a different engine. (as some rumors hinted before me, I think it's Unity)
Various points to back up this idea of a new engine: bigger scale fights, less details on each model, fixed cover system, more focus on bigger units and "elitè" units. Unity would be perfect for this and it would provide a much more optimized engine to manage big battles.
I think the game will be closer to the DOW1 design but also closer to the Supreme Commander scale rather than the COH scale: if this happens to be the truth we could expect a pretty different game compared to what we are used to see from Relic; my guess, with the few information we have, is that DOW3 will be a sort of hybrid RTS/MOBA with a focus on team games and macromanagement (where micro would be mainly accomplished from units positioning and Elitè units unique abilities).
It could represent a smart move in some way since it would mean having an easier to play and on bigger scale Relic game that would be designed to be more appealing and easy to approach for a wider amount of people (kinda like Arena is in the Total War franchise). On the other side it's a risk, they might be further "dumbing down" the game mechanics and a lot of fans might not like it.
Personally I am looking forward to see a game with a different approach compared to Company of Heroes so I am totally interested in the new project. Graphics might not be as good as previous games but if the scale is actually bigger (and also zoomed out more) it wouldn't really matter.
Let's wait and see more info about it
PS: Obviously for a COH3 I would want to see a better version of COH1, more punishing and more rewarding for good micro play. Having two different paths for their franchises to cater two different audiences might actually be a good long term plan!