It's great that I can get an audio file sent as an email when I get a new voicemail. But after listening to the audio file, deleting the email does not remove the voicemail so I still have to access the voicemail service via my phone or TV to really delete it.
Implementing the voicemail box as an IMAP mailbox would solve this. I could access this mailbox via my mail reader and directly delete voicemails. Your telephone and TV interfaces would of cousre also need to be changed to use IMAP instead of whatever properietary protocol you use today.
I hope you will consider this idea for the (not so distant) future.