Update: A Vault 2013 version of this app has been released.
The problem with writing cool sample apps is that they have to be ported over to the new release. So I took the opportunity to make some improvements and show off the new API features.
Effective Folder Permissions is a set of commands that allow you to view the folder permissions on a per-user basis.
Vault Workgroup/Collaboration/Professional 2011
Run the install and start Vault Explorer. There will be a new sub-menu under the tools menu and a new command in the folder context menu. You must be an administrator to run any of the commands.
Additional information can be found in the readme file, which is installed in the "Explorer\Extensions\EffectiveFolderPermissions" folder under your client install directory.