Here’s your quick weekly summary of all the latest social media news, including changes and new features on Facebook, Twitter, Google+, YouTube, LinkedIn and Foursquare:

New estimates from eMarketer show that Facebook’s worldwide user base is seeing the biggest expansion in India, Brazil and Russia, as well as the Middle East and Africa. Facebook will top one billion users worldwide in 2013, and reach 1.26 billion in 2014.

Target just teamed with Facebook to launch Cartwheel, a new digital savings program. Beginning on Wednesday, Target is offering 700 new deals “with a social twist” — every time a user claims a deal, an automatic post is generated in their Newsfeed on Facebook. Consumers can find and share deals with friends on the social network, as well as redeem offers in store.

Internet Media Labs today announced the launch of oneQube SmartStream, a free Twitter chat platform designed to support the hundreds of active Twitter chats that were rocked by this week’s news about the imminent demise of TweetChat, a popular chat client that will soon stop working as a result of Twitter’s latest API changes. The SmartStream team says their platform is fully compatible with the new Twitter API rules. SmartStream is part of the oneQube SocialRM platform, which is currently in private beta.

Drinking beer doesn’t just make it easier to meet people – now it also helps you make new Facebook friends. Budweiser’s new Buddy Cup connects beer drinkers on social media: using a built-in chip integrated with Facebook, one clink of their glasses and users become Facebook friends.

TweetChat has posted a notice at the top of its site announcing that “Twitter is changing the way services like @TweetChat deliver data to users. In the very near future, TweetChat will most likely be unable to continue to provide our service.” The problem, apparently, is the latest round of Twitter API changes, now scheduled for June 11, which will prevent applications from using JavaScript to pull data from the Search API

Here’s your quick weekly summary of all the latest social media news, including changes and new features on Facebook, Twitter, LinkedIn and Instagram:

When I first started writing about contextual influence measurement tools, the key advantage they had over personal influence measurement tools like Klout is that they measured influence in the context of a specific topic. Today we’re seeing a whole new generation of tools and platforms that take it even further by letting marketers see not just the individuals who are influential in a given topic, but to understand the whole community of relationships around that topic.

Today, Traackr, one of the most mature contextual influence measurement platforms, introduces something it calls Influencer Network Analysis (INA), a new capability that allows marketers to see how influence travels to and from an individual influencer.

Facebook released its first-quarter earnings report on Wednesday, showing strong mobile growth once again. Here are the highlights:

The Weather Channel is premiering the ‘Twitter stunt’ as a marketing tool in a fun campaign to promote #TornadoWeek. This week, the Weather Channel’s interns are working at desks that have been placed in a “Twitter-powered tornado.” The more tweets that are sent with #TornadoWeek, the higher the office tornado’s wind speed will rise.