http://www.macnn.com/articles/09/06/16/youmail.app.for.iphone/
YouMail releases visual voicemail app for iPhone
updated 10:15 pm EDT, Tue June 16, 2009
YouMail app for iPhone
YouMail has released an iPhone version of its Visual Voicemail Plus application. The software provides users with the standard caller display, along with information not loaded into a user's address book. The application also converts voicemail messages into readable messages and can forward voicemail to other contacts. Users can change their greetings in order to inform callers of their whereabouts and when they will be available next.
Voicemail can be saved, recovered and organized within the iPhone application. The iPhone app connects with the desktop version of the application, allowing users to sync messages and block unwanted callers.
YouMail is immediately available from the App Store for free.
Fresh-Faced Recruit
Joined: Jul 2003
No it's not...
Well, the link in the article doesn't work, and there's nothing in the App Store, so I'm guessing it isn't available immediately for free.