I like phone calls, but I HATE voicemail. When I was a network admin I strongly encouraged people to contact me via email if they wanted a response. And I had my office phone permanently forwarded to my cell phone, not because I wanted all people to be able to get a hold of me at all times, but because I simply did not want to have to manage the voicemail on my desk phone. Ever. The problem with voicemail is, if it's not an emergency it doesn't move to the top of my to-do list, but voicemail is organized so poorly that I'm liable to forget about it entirely and never actually address whatever the person was calling me for. I mean, sure, when I listen to the message I push the button to save the message, but if I ever want to listen to it again I have to get by all the other saved messages in order to hear it.
Visual Voicemail is by far the biggest innovation brought to the table by the Apple iPhone, as voice messages are displayed onscreen exactly the same way email is displayed in a typical email client, and you can listen to messages in order of importance, or file them away based on whatever criteria you want. It's the way email works, but more importantly it's the way any type of messaging system should work.