Just mashed up a quick applescript to post the currently selected news item in NetNewsWire to Twitter. The code is highly influenced from TwiTunes, (which posts the current track on iTunes to Twitter) and the Shorten URL script from iconmaster. So all credits goes to them.
By default, the contents of the tweet is set to the title of the news item and the URL is shortened using is.gd and you can easily customize it.
The script needs you to save your Twitter login credentials in your keychain or else you will get an error. To do this, tell Safari to save your login details to Keychain while you login to Twitter or you can do it manually in the keychain app by selecting ‘New password item’ and set Keychain item name as http://twitter.com and fill in your Twitter username and password in the following fields.
Installation
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.
Code
If you want to have a look at the code:
if index of selected tab = 0 then
-- We're looking at headlines, so just get the headline URL
set feed_url to URL of selectedHeadline
set feed_title to title of selectedHeadline
else
-- We're looking at a web view tab, so we need to know which tab
set i to index of selected tab
set i to i + 1
-- Get the tab's URL
set URL_list to URLs of tabs
set title_list to titles of tabs
set feed_url to item i of URL_list
set feed_title to item i of title_list
end if
-- Build the GET request for the is.gd API
set feed_url to "http://is.gd/api.php?longurl=" & feed_url
-- Submit the GET request and copy the results to clipboard
set cmd to "curl " & feed_url
set feed_url to (do shell script cmd)
end tell
-- change the status message to your liking here:
set tweet to feed_title & " " & feed_url
-- let the user edit
display dialog "Edit your Twitter status" with title "TwitNews" default answer tweet cancel button 1 default button 2 buttons {"Cancel", "Send"}
set tweet to (text returned of result)
-- get login from keychain
tell application "Keychain Scripting"
set twitter_key to first Internet key of current keychain whose server is "twitter.com"
set twitter_login to quoted form of (account of twitter_key & ":" & password of twitter_key)
end tell
-- post to twitter
set twitter_status to quoted form of ("status=" & tweet)
set results to do shell script "curl --user " & twitter_login & " --data-binary " & twitter_status & " http://twitter.com/statuses/update.json"
Hope you find this useful and feel free to make any changes as you need.
UPDATE: You might want to check this post to assign a keyboard shortcut to the script.
UPDATE: There is an updated version available with some new features. Please see this post.
dab Says: 
vandy Says: 
Gulumbit Says: 
Flanker Says: 
March 24th, 2009 at 11:20 pm
many thanks, was looking for something like this