Yup... I had this same problem. The new voicemail icon was stuck.
I had VZW delete VV from my account... then the tech called my Storm and left a voicemail, I called in and deleted it... that cleared the voicemail icon... then we added the VV back onto the account.
worked like a charm!
And you have to do it in that order.
1. Delete VV from account
2. Leave vmail, then delete vmail to clear notification icon.
3. Add VV back to account.
If you do step 3 before doing step 2... it won't clear the notification icon. (we tried this).