dlvr.it will add Google+ (Google Plus) as an output as soon as Google makes a Google+ posting API available. On 9/15/2011, Google publicly announced a 'Read Only' API - that allows public data to be read from Google+. Google has still not published a "Posting" API that allows posting of items to Google+.
On 11/7/2011 Google announced Google+ pages for Businesses. However, Google has still not opened an API to allow for dlvr.it or other 3rd party apps to post to Google+.
We'll announce additional / official Google+ integration on our blog (http://blog.dlvr.it) and via @dlvrit. You can follow conversations surrounding this feature in our Feature Requests forum, here.