I am quoting Fran Lupo from Facebook who found a way to fix twitter-facebook connection. If your twitter is no longer updating your Facebook status, this is a way to fix it. It worked for me.
Fran Lupo
Here is the fix – this is exactly what fixed mine….The easiest way to fix this is by disconnecting and reconnecting the Facebook application to your Twitter account.
To do this:
1.From the Settings Menu on Twitter, visit the Connections tab.
2.Find the Facebook application and click the Revoke Access link below its name and sign out of Twitter.
3.Log into Facebook and visit your Privacy Settings from the Account drop down menu on the top right
4.At the bottom, click Edit your settings and then Edit settings
5.Find Twitter and click it…then Edit Settings then click Remove app
6.Sign out of Facebook and close all browsers.
7.Delete your history, cookies & temporary internet files. Do NOT perserve favories websites data.
8.Sign back into facebook.
9.Navigate to http://apps.facebook.com/twitter/ to install the app anew.
10.After you have done the above steps, make sure theupdate facebook box us NOT checked on the Twitter app page
11.then send a tweet from your twitter page (which won’t appear on FB)
12.then re-check the box on your facebook twitter app page and tweet again from your twitter account…That should do it!