"I hate voicemail," says David Hayden, founder of Pana.ma, a startup that sends voice messages like Twitter sends Tweets.

I'm puzzled and also gratified. I hate voicemail too, but puzzled by the difference between what Pana.ma does and voicemail. On the surface, one looks very much like the other.

"With Pana.ma, my email is less, I text less, I have fewer meetings. It has made me much more productive," says Mr Hayden.

I'm intrigued at how a voicemail-like service can do all that. I'd love to be able to cut down on my email, texting, etc, too.

But first, some background information: David Hayden is founder of Critical Path, he was also co-founder of Magellan Search, and much more...

Pana.ma voice messaging service allows people to send voice messages to each other, up to 3 minutes in length. It is available on the iPhone, Blackberry, and Android phones.

Here are some notes from our conversation:

- Pana.ma allows you to have more conversations, but they are asynchronous conversations.

- We did some studies among teenagers and they would rather text because they don't want to have a conversation. Pana.ma allows you to have a conversation asynchronously and that makes it easier and more appealing than an actual phone call.

- Voice conveys emotion, it conveys a lot more information than text.

- We looked at the limit of a voice message, in a similar way that Twitter limits the size of messages and we settled on 3 minutes, which is probably a little too long.

- We will add a transcription service in the future.

- We have 20,000 users since we launched in January, with no publicity.

- Pana.ma has replaced meetings for me. I am exchanging voice messages all day long with my team. We rarely talk directly , and that's more productive because the PMs (Pana.ma Messages) setup the voice calls.

- We even PM when we are in the office and just a few yards from each other. It's more convenient because you can take your time to reply.

- It surprised us at how social this has become.

- You can add people to a thread or remove yourself from the thread.

- Twitter is not conversational, it is a broadcast medium. We don't consider Twitter a social network.

- We will make our API available in about three weeks.

- The experience is surprisingly pleasurable, fun, and sticky.

- You'll be able to insert PMs into documents.

- It's great at helping you manage your time. When I'm with my 9 year old son, he doesn't want to see me using my iPhone. I can quickly send a PM.

- Revenues will come from a variety of additional services such as longer messages, group tools, voice modification, archiving, etc.

- We raised a seed fund of $3 million and we will raise another round this summer.

- We have a development team of 6 people in Argentina, and there are 8 in this office.

I can see how Pana.ma is similar to a voicemail but could be much better. Texting someone is one way to avoid having a conversation when all you want to do is to communicate something. Up till now, we haven't been able to do that with voicemail.

Leaving a voicemail takes forever, first you have to wait for pickup, then sit through a message, then sit through the message menu, then when you think it's finally time to leave your message, you hear, "And to send a fax press 3... to page this person press 4."

Pana.ma saves you at least 70% of the time to send a voicemail -- and you are guaranteed not to have to speak to anyone directly. I'm going to give it a try.