Editor’s Note: The Social Media RoundUp is a weekly feature of Information Space.

image by thenextweb.com

image by thenextweb.com

Facebook took over headlines this week when they launched a new friend-tracking feature on their social networking site. The feature is officially called Nearby Friends and its purpose is to help you discover where your friends are in real time. If you turn on Nearby Friends, you’ll occasionally be notified when friends are nearby, so you can get in touch with them and meet up. For example, when you’re headed to the movies, Nearby Friends will let you know if friends are nearby so you can see the movie together or meet up afterward. Nearby Friends is an optional feature that can be turned on or off in your settings.

Twitter also had a big launch this week, but theirs is still in the beta stage. This week they unveiled mobile app install ads. Twitter is unveiling the the mobile app install promos with a slew of beta advertisers, including Spotify, HotelTonight, Kabam, Deezer, SeatGeek and GetTaxi, among others. This now allows users to discover and immediately download new apps from ads that are natively placed in their feed.

In stop motion video news, Vine cofounder Colin Kroll announced via Twitter that he is stepping down from his position as Vine’s general manager.

Let’s all congratulate LinkedIn as they just reached 300 million registered users! LinkedIn is rapidly growing, and the company plans to continue doing so with mobile as a focus.  With continued growth, the company will steadily improve their site and who knows, the 400 million mark may come sooner than we think!

Do you have any stories to add to the list? Let me know in the comments below!