It’s simple. Create a (free) account and then call one of the access numbers (there are several countries on the list). Enter the PIN you received upon registration, and your phone is synched.
To make a recording, call an access number and record 140 seconds of audio. You can then tweet the message, include it in an email or on a web page, share it on Facebook or Digg or del.icio.us. Listen to my test case (on the Trottr site). Or download the mp3. How do you see this tool being used?