I have upgraded the package to SQL 2008 and plan to publish it someday. We are skipping the SQL Server 2008 R2 in our shop because of Microsoft's requirement for a new license to use the R2 release.
I did this upgrade a while ago and did not get any errors. I have a seperate package (never published) for pre SQl Server 200 instances that gave me warning and required a change to the multiserver database connection.
Upgrade gave this warning:
Warning 0x4020f42c: : The Maximum insert commit size property of the OLE DB destination "OLE DB Destination" is set to 0. This property setting can cause the running package to stop responding. For more information, see the F1 Help topic for OLE DB Destination Editor (Connection Manager Page).
Not able to access SQL Server 7 through multiserver. Created new multiserver to use Microsoft OLE DB Provider for SQL Server.