Mark Morowczynski has just blogged about this enterprise hotfix rollup so I wont repeat what's already been said, but if you have Windows 7 or Server 2008 R2 then you should go apply this.

http://blogs.technet.com/b/askpfeplat/archive/2013/03/12/slow-boot-slow-login-sbsl-hotfix-rollup-for-windows-7-and-server-2008-r2-available-today.aspx

 

Jeff Stokes who was one of the key contributors also talks about it here:

http://blogs.technet.com/b/jeff_stokes/archive/2013/03/12/download-this-kb-now.aspx