Purpose of Media module If I am using the IMCE file uploader combined with CKeditor, is there any point in installing the media module?

Or does media replace the imce when wysiwyg module is used?
The Media Module (2.x) uses the File Entity module. Files become 1st class citizens in your Drupal installation just like a Node or Entity or a variable. A FileEntity can be queried using Views for instance.

IMCE (to my knowledge) is simply a file browser (bridge) for your server compatible  with TinyMCE and I suppose CKeditor now. Files are just files on the system and drupal isn't 100% aware of them and their meta-data.

If you only need to browse files then IMCE has its usages. If you want something more meaningful and integrated with Drupal as a whole look at Media, and maybe like Media Browser Plus.