I often tell people about organisations that have outgrown their SBS system.  Many people are not aware that the answer to this problem is the Transition Pack.

For those who are, they often worry about "what is involved" and "how long will it take".  Believe it or not, I have not used the transition pack yet, so while my copy is on order, I thought that I would share this resource to help you understand more.

It covers everything from licensing, to documentation through to process.

http://blogs.technet.com/sbs/archive/2006/01/12/417350.aspx

Let me know what you think

David