With the announcement of the December 2008 Cumulative Update and the changes in the software update model it brings, we felt it was a good time to revisit the topic of slipstreaming. This post provides the process for creating a slipstream installation source that uses the December 2008 CU as an example. You can simply replace the December 2008 CU with the February 2009 CU, April 2009 CU, and so on going forward because the process will be the same.
Read the article at blogs.msdn.com/sharepoint