I remember seeing a very early CTP of Yukon and the new DTS. I was very exceited to see a parallel property on the loop container which would allow the contents of the container to be executed in parallel.

If you've used the RTM on Yukon you will know that there is no such property. Unfortunately it was too complex to be implement.

However you can still get parallel execution by using multiple tasks or by having multiple paths in a data flow.

For more details read this post

http://blogs.msdn.com/sqlperf/archive/2007/05/11/implement-parallel-execution-in-ssis.aspx

This is cross posted from my SQLBlogcasts blog which can be found here, http://sqlblogcasts.com/blogs/simons/SSIS - Parallel processing