I have 2 sites with 2 domain controllers and 1 exchange 2003 server per site. I have 4 RUS entries...2 that point from site 1 exchange server to each site1 DC. 1 points from site2 exchange server to site2 dc. The 4th is the enterprise RUS which points from site1 exchange server to site1 DC. The 2nd DC in site 2 is new, and i have not yet had a chance to update RUS, but i want to be sure this is something necessary.
I have no replication issues between the sites...as they are connected via point to point T-1.