[Thex]

What does the fog of war actually prevent though? I see lots of "can't see out/in" comments, but what would this actually prevent/enable?

Would it prevent a casual view of a galaxy/cluster? - I'd say yes
Would it prevent a scan on a planet in the fog, even if you entered co-ords of a known planet - I'd say yes
Would it prevent and attack on a planet in the fog - I'd say no attacks could still be run, but without scans it would be dangerous.

However I'm concerned that that more organised allies could use/abuse this as they share scans and have dedicated scanners more capable of covering areas someone else might find is in the fog of war. Even to the point where they organise attacks from planet who cannot see anything and have deliberately used the fog to hide. However I don't know if this is a good/bad thing because either it won't be implemented or the size of the universe will mean that the fog will only be relatively small - even for individual players or small intel-challenged allies.