As has been already reported in Macworld, Automator actions that talk to iTunes all broke upon the release of iTunes 10.0. This is because each action specifies in a text string in its Info.plist file that it requires iTunes version 4.6 or higher, and alphabetically, '10.0' is smaller than '4.6.' I frequently use 'Add to iTunes as a Spoken Track' (activated in System Preferences » Keyboard » Services). Here is how I got it working again.
'Add to iTunes as a Spoken Track.workflow' is found in /System/Library/Services. Navigate to that location and double-click the workflow file. Don't Panic! We are not going to modify this file; we're just looking for error messages when it's opened in Automator.
Automator complains that the actions 'Import Audio Files' and 'Add Songs to Playlist' could not be loaded because the application iTunes is the wrong version.
Navigate to /System/Library/Automator. WARNING: Do not modify files found under /System! Copy 'Import Audio File.action' and 'Add Songs to Playlist.action' to a convenient location in your User area. After copying, right-click on one of those files and select 'Show Package Contents.' Inside the package you will find a Contents folder within which is an Info.plist file. Open this file in your favorite text editor. Look for a section of text that looks something like this:
<array> <dict> <key>Display Name</key> <string>iTunes</string> <key>Resource</key> <string>com.apple.iTunes</string> <key>Type</key> <string>application</string> <key>Version</key> <string>4.6</string> </dict> </array>
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http://hints.macworld.com/article.php?story=20100903004553923