Re: Skipping versions?
"TheVogon: Multiple DCs is rather an unlikely scenario when you only have a single server - indeed, as I recall it was *prohibited* on the small business SKUs originally"
If you ONLY have a single server, then you have no services to protect against authentication failure if that single server is down, and you would have to rely on restore from backup or a reinstall if you have a complete failure. An additional domain controller server with SBS has always been supported - ever since Windows NT. See http://blogs.technet.com/b/sbs/archive/2007/10/04/debunking-the-myth-about-additional-domain-controllers-replica-dcs-in-an-sbs-domain.aspx - and has the follwing potential benefits:
•Redundancy:
◦If the Small Business Server cannot be contacted but another DC is available users can still authenticate.
◦If DNS is also installed and the zone for the internal domain is being replicated to all DCs/DNS servers, redundancy will be provided for local and public DNS namespace queries.
•Disaster recovery:
◦It is not necessary to rebuild your entire Active Directory domain if the Small Business Server crashes and you don’t have a good system state backup.
•Improved user experience:
◦If additional DCs are placed at remote sites and also made Global Catalog Servers, remote users can logon more quickly and reliably, and locate objects in the domain more quickly.
"let's make that new platform Google Apps"
You get what you pay for. If you want cloud, Office 365 is a better product in pretty much every way.