Twitnews is a project mainly written in ..., it's free.
Applescript to post the currently selected news item in NetNewsWire to Twitter.
Applescript to post the currently selected news item in NetNewsWire to Twitter. Asks for your twitter username and password when run for the first time, and saves it to the system keychain. Script also trims the URL to the news item using Tr.im URL shortener and lets you edit the tweet.
Download the script TwitNews, uncompress and drop it into ~/Library/Application Support/NetNewsWire/Scripts. Now you can access the script from the scripts menu on NetNewsWire.
Please visit my blog for more details : http://blog.tinucleatus.com/?tag=twitnews