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Tweetbot for Mac is still in its alpha stages, but is available free for download and works great with NC. In fact, I've gotten more out of Tweetbot with NC than regular Twitter. Mentions, new followings, etc.


Google Chrome works every once in a while, if you have Gmail open in the browser and have the option turned on. However, it only appears as a banner, and doesn't stay in the NC listing for some strange reason.
 
I forgot to mention, Tweetbot has to be open to receive notifications. However, you can open the app and hit the red X and it'll remain open in the dock.
 
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