SQL Server 2008r2 replication from multiple sources I am currently rearchitecting an application so that each of seven businesses will have there own "live" SQL Server 2008 database and at scheduled times during the data the data from all seven databases will be replicated to a master reporting database.

The question I have is do I need to do anything within the replication to maintain the Foriegn Key relationships from the source database tables or will replication take care of it for me?
SQL Replication isn't going to handle that for you.  You'll have to setup a very custom replication type system, possibly using SQL Service Broker to handle the merging of data into a single system for reporting.