You can view all data in Management data warehouse for all instances that upload collected data to the warehouse database using "Management Datawarehouse overview report"
You can view this report by following these steps1) Open SQL Server management Studio, Connect to SQL Server instance that is hosting Management data warehouse database (MDW)
2) Right click on MDW database, Select Menu Reports -> Management DataWarehouse -> Management Datawarehouse overview
3) On right pane you will see a report that list all the instances that upload collected data to this MDW. for each instance, you can launch the hyperlinks for reports that lets you view data collected by system collection sets
Related Connect Feedback : http://connect.microsoft.com/SQLServer/feedback/details/648960/datacollector-for-sql-server-2008-view-reports-issue
Is there a way to publish the reports to SQL Reporting Service? We have Hundereds of DBAs that want access to reports, but we don't want to expose or SQL Managment Server.