Twitter () is about to announce that it is launching major upgrades to its Facebook () and LinkedIn () applications, bringing added functionality and integration between Twitter and two of the world’s largest social networks

The new Twitter app for Facebook, which will be available here at 3:00 PM PT, not only allows you to syndicate your tweets to the world’s largest social network, but now has a feature that allow users to see which of their Facebook friends are also on Twitter and choose which ones they want to follow

The new feature could be huge: it brings existing Facebook connections into the Twitterverse, which is likely to spur new levels of engagement and growth

The microblogging startup is also announcing updates to Tweets, LinkedIn’s Twitter application

It also includes a feature that lets you see which of your LinkedIn connections you follow and automatically follow the ones that you don’tRead more at mashable.com