Android DIGITS v1.0.253
When recording a new greeting for voicemail, there is no opportunity to review it before it is uploaded. If you aren't real familiar with the device DIGITS is running on, your greeting can end up pretty unsatisfactory. Particularly using built in microphones.
Basically I had to wait for it to upload (which was fairly quick), then call my number from another phone to check it.
In my case, my greeting was too loud so I recorded another. That one got a dog bark included. On subsequent attempts to record a new greeting, I got "Greeting upload failed" alerts. This may resolve itself after a period of time - but for now it's been about 10 minutes and I am still unable to modify the recording.
The application needs to allow you to verify your greeting before it is uploaded.