I am migrating from SBS 2008 to SBS 2011 but the Microsoft documentation does not yet exist. Has anyone done this yet? What are the recommended steps/procedures?
Microsoft has now posted the documentation on how to do this http://technet.microsoft.com/en-us/library/gg615506.aspx
SBS 2011 just released to manufacturing last month (it's not even on my Partner access yet) so it looks like there isn't a lot of third party posts about migrations. From the few that I have it looks to be similar to the migration from SBS 2003 to SBS 2008.
I think the only exception would be the migration from SBS 2008 to SBS 2011 Essentials which is a cloud based offering.
http://www.sbsfaq.com/?p=2351 http://blog.mpecsinc.ca/2010/12/sbs-2003-to-sbs-2011-microsoft.html http://blogs.technet.com/b/sbs/archive/2010/12/13/windows-small-business-server-2011-standard-releases-to-manufacturing.aspx
I did this a while back using the Microsoft method, there is details inside the SBS 2011 Administrators Companion that outline how to do it.
I must say, having followed it step by step, I did run in to a number of catastrophic errors so I would recommend building a test environment imaging your existing SBS 2008 server, restoring it to your test lab and trying it for real.