As of today, Google Voice has been added to Google Takeout, a service which allows you to quickly export data from specific Google applications. You can now export voice communications (transcripts too) with voicemail and greetings as mp3s, phone numbers as a vcard, and text messages as html.
The service lets you create a quick full archive of all your data, or select just Voice or another service. You can check out Google Takeout now, which also allows you to download data from other applications including your contacts, stream and circles from Google+, Picasa Web Albums, and your Google Profile info. (via Google Data Liberation Blog)
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