Ignoring the specific game I think it says good things about the PS4 hardware. This game is a launch title and hasn't had the time to be finely tuned to the production hardware. I suspect resolutions will go up from the 720p on the Xbone and the 900p on the PS4 in future games. That bodes well to the PS4 actually hitting the target 1080p@60fps for this generation. DigitalFoundry seems to think the lack of sharpness in the PS4 pics is a result of upscaling so if more finely tuned games in the future manage to hit 1080p natively then that becomes a non-issue because no upscaling will be necessary. For the Xbone I'm sure it's resolution will go up as well as games are better tuned to it's hardware but I'm not as confident it will hit a full 1080p@60fps. I think before DigitalFoundry was saying 900p was probably more realistic on the Xbone then upscaling to 1080p (thankfully it seems to have a better upscaler than the PS4). I'm not trying to badmouth the Xbone, they do very well in other areas such as better audio and motion/voice controls but it seems clear that (at least in this case) the PS4 has the graphics lead.
I think that until MS or 3rd party developers prove it with actual software that runs at higher res, your assumption makes a lot of sense.
If we just take what we are seeing at the moment, it would lead me to think that the ps4 will always have an edge in that area.
Now since MS does at least have Forza running at 1080p/60, its clear that the X1 is capable of reaching that level. I think the lingering question is can they do that for many games like the ps4, or will there be cuts that force lower res.
Same goes for the ps4 in a way. We have not seen a 1080p/60 title yet (Is Killzone?) and we don't know how many games will be using that.