I saw a few other suggestions on this but I also want to suggest that there should be some type of voicemail report under the call reports. Managers should have visibility into voicemails to ensure that team members are handling voicemails. Also, there should be an option to retrieve deleted voicemails as well.
Goto really needs to look into enhancing this and making this an option as I know I am not the only client who would have a need for this.