I was using an automated build to package up a SharePoint App when I received the following error:

Missing or Invalid property value for $(MsDeployServiceUrl)

I used grepWin to search through our project files looking for any references to this value and found none, leading me to initially believe that it was in fact missing.  However, I was able to successfully package the app using a different publishing profile which led me to believe something else was wrong.  After a bit of digging, I noticed that the publishing profile that worked had a Client ID set, but the one that did not work had a blank Client ID (not sure how it got removed).  After adding the Client ID value back into the publishing profiles everything started working again.