http://drupal.org/node/1549486#comment-6017132

I believe if these 2 modules were to merge or at least share some techniques, messaging on D7 could really be great. Privatemsg has FieldsAPI, message by role, hopefully Messaging module integration, etc. Maybe the developers there can provide their expertise/knowledge with the Drupalchat developers to integrate into this module to be something more like Facebook messaging. Use FieldsAPI to add attachment support, etc.

Don't want IM? Disable it.
Don't want inbox? Disable it.