Microsoft recently announced that the Windows Server 2012 editions will not be seeing a “Small Business Server Edition” - they have simplified the licensing. Basically, there will only be four editions – Datacenter, Standard, Essentials and Foundation. For more details, see Microsoft’s post on the official site and also check out the licensing datasheet.
There is also an FAQ available with most of the common questions answered. Specifically, I would point to Q33 because this will sign the end of an era with Windows Small Business Server.