There are a couple of services that do this including SimulScribe,
SpinVox and Phonetic.
Justin S. Wilson wrote:
Found this interesting:
Vtxt <http://www.callwave.com/landing/vtxt.asp> , a new
service from CallWave that transcribes voicemails and sends them to you as
text messages or e-mails. All you have to do is forward your calls to a
unique phone number supplied by CallWave. Your messages are processed by an
automated speech-recognition engine and sent to you in about four or five
minutes. You can choose to receive the transcriptions as text messages,
e-mails or on the CallWave website.
Justin S. Wilson <[EMAIL PROTECTED]>
Technology Services - WISP Consulting - Tower Services
WISPA Wireless List: firstname.lastname@example.org