PlanetsCentral

Explore map on the other hand ... well for gameplay it doesn't really matter. It's different, sure. However it's not crucial. :D

IBTD it makes a lot of a difference IMHO here are just a few quick points:

1. Hyperjumps are clearly easier with the full prior knowledge of the cluster and borgs can much easier sneak up to you.

2. Big meteor impacts can now be pin pointed

And if you want some 'realistic' metaphor think about it as event horizon and fog of war. ;)