Nice article.

Myself, I prefer developing the package to allow easy migration, rather than designing a system to do the migration.

In DTS terms, I usually use a database table that holds all the global variables. Then a short ActiveXScript coupled with a Dynamic Properties task will allow super easy migration between environments. Having the global variables in a table makes it easy to adjust things like connection properties and file locations without going anywhere near the DTS Designer.

At a basic level, this approach is the same as the Package Configurations available in SQL Server 2005 Integration Services.