As far as I've noticed...the next time a new message comes in, the Message Waiting setting will go back to yes on its own.

One issue I find is that when you delete the messages directly, the MWI (message waiting indicator) doesn't reset. One run-around that works for me:

-Listen to new message
-If you want to erase, actually save message (9) to folder (1) old messages.
-Hang up.
-At this point your MWI will reset (within a few minutes).
-You can at a later time erase all messages in the "Old Messages" folder.

Also having a voicemail problem over the past month.
Messages come in, but I don't get any email notification.

Edit 12/8/10 Happened again today. This is beginning to be a large problem.

No one else having this problem?

12/21/10 Still happening - got a voicemail but no email. This is a major problem for me.
Is there any way to formally report a problem to voxalot, or is this forum it?

I personally have not seen any problems with Voicemail to email messages.
I am assuming that you have checked the usual things:
1) valid email address registered and verified in Voxalot
2) that the message is not going to your spam folder
3) that you do not have some kind of spam filtering service that is deleting your spam messages.