I'm embarking on a project in which users will author, save, and share their own maps over the web. We will provide them with a large number of feature classes, but users will effectively author their own maps, map symbologies, etc. Furthermore, they will create and edit their own feature classes, which they can both map and share with other users.
The model for AGS map services seems to be: author a map in ArcMap, save an MXD/MSD, publish. I'm struggling to understand how this can help us build a dynamic web mapping platform as described above. Can anyone offer some tips on how to go about it?