I wrote an application called VyMail that interacts with the YouMail service and provides a visual voicemail interface no your blackberry. Basically a free alternative to the default visual voicemail application that Verizon provides. More information is here: joekrill.com - VyMail - YouMail application for Blackberry devices
, and the direct OTA download link is: www.joekrill.com/vymail/ota/
(I can't post URLs directly yet, sorry). I posted this on the CrackBerry forums and got a great response, so I thought I'd spread the word a little more.
This will run on any Blackberry running OS 4.1 and above, actually.
It's fairly light on features at the moment, but I plan to add much more to it.
There is also an audio issue with anyone running the 220.127.116.11 verizon software. There's a pretty major flaw in that version which prevents me from routing sound through the speakerphone speaker, so it will only work through the headset in that case.