The target market appears fairly clear now. Mac Mini Server is targeted at small businesses. However, when you have Phil Schiller out there promoting it as a home server it clouds their strategy.
When I first read the Business Week article, I immediately thought they were targeting enthusiasts who wanted a Mac version of Windows Home Server.
Heres my feature list for a Mac-based home server.
The server would:
Perform backups of all my Macs daily automatically
Serve out iTunes media without running full-blown iTunes (think iTunes server for OS X Server, a system preferences service that automatically perform home sharing tasks like copying over ratings, new purchases, etc with all my client machines and serve my Apple TV)
Serve out a main iPhoto library to client Macs and automatically copy new photos from those iPhoto libraries to the server
Automatically create a Back to My Mac Web site where you can access your files including music, video and pictures via the Web
Monitor disk space and push software updates out to all my Macs
Enable roaming profiles, so anyone in my household could log-in on each Mac and have all their settings, etc.
Maintain a main iCal and Address Book that would be accessible on every household Mac
and package all this into one tight, easy-to-use OS X-based package.
But thats not what Apples offering currently.