.LRN 2.0 (release within a month) will have multiple ways to sync user data with external sources.
* Batch account synchronization though OACS-specified format
* Batch account synchronization through IMS 1.1
* Real-time account synchronization framework
* Real-time account sync driver for LDAP (not sure how far we are on this, but it is funded and Greenpeace is going to be using it)
Maybe we will find a champion to look into group (course and community) synchronization for .LRN 2.1
Disk space is getting cheaper on a monthly basis and often the value of "retired" user contributions warrants the fractions of a cent it may cost to save it. Deactivation fits our relational data model better than deletion, but if we are forced to removed a user and all dependent contributions it might make sense to actually leave something in the DB (e.g. "users contributions deleted") so that other members of the community are not confused (e.g. if your contributions to this discussion disappeared, it would make it confusing for a new user).