This week, Microsoft shipped beta versions of its next-generation Windows Small Business Server (SBS--code-named Cougar) and Windows Medium Business Server (code-named Centro) products. These products are currently available only via private beta.

Both Cougar and Centro will be 64-bit products that run on only the x64 hardware platform. Cougar is the Longhorn-era version of SBS and includes integrated versions of Longhorn Server, Exchange Server 2007, SQL Server 2005, ISA Server 2006, Windows SharePoint Services, and System Center Essentials.

Centro is a similar product, but it's aimed at midsized businesses. Unlike SBS, Centro will be installable on multiple servers. The product includes versions of Longhorn Server, Exchange 2007, SQL Server 2005, ISA Server 2006, and System Center Essentials. Both Cougar and Centro are due out in 2008, after Microsoft ships the standalone versions of Longhorn Server.