By Robert Schoon (r.schoon@latinospost.com) | First Posted: Dec 21, 2013 09:18 PM EST

This week, Facebook joined the S&P 500 while founder Mark Zuckerberg personally made more shares in the company available for purchase, Google and Facebook battle it out with different year-end roundup services for their users, Twitter will let Vine users get vanity URLs, and it turned out that Instagram's new ads are a success. Let's dive into Social Media Saturday!

Facebook

The biggest news of the week was probably Facebook's being added to the Standard & Poor's listing of 500 significant stocks. The move represents a win for Zuckerberg, who, in response to the new listing, offered a little more than 41 million of his personal shares in the company for sale.

He's not cashing out of his own company, but rather purchasing Class B stock and selling Class A stock to "satisfy taxes that he incurred" from the Class B buy. In any case, the S&P 500 listing also confirms Facebook's status in the marketplace, after a rough IPO in 2012 and a lot of skepticism about the company's public worth.

Instagram

Speaking of Facebook Inc.'s financial successes, Facebook-owned Instagram released its first results after enabling ads on the photo-sharing network earlier in November, and according to the numbers, the ad initiative worked - despite making some Instagrammers instantly angry.

The initial four brands that Instagram tracked on the social media network were all successful at delivering the messages they sought to distribute, resulting in a ten point incremental lift in brand message awareness and an uptick in brand association. Levis, for example, reached about 7.4 million Instagram users in the coveted 18-34 year old demographic in just 9 days, while Ben and Jerry's Ice Cream reached nearly 10 million in that demographic in 8 days. Instagram is planning more optimization to attract marketers after calling the initial results "promising."

Vine

While Facebook focused on the money and marketing aspects this week, Twitter went after users with a new option for its video-sharing sub-network, Vine. Starting yesterday, on Friday, Dec. 20, Twitter turned on so-called "vanity URLs" for its users with verified accounts, so that people can search the web for "vine.co/username" instead of an endless string of numbers.

For those who aren't famous enough to have a "verified" account, Vine will enable vanity URLs on Dec. 23. For those who wonder about configuring your Vine URL to match your Twitter profile, Twitter says it's automatically reserving matching profile names for the vanity URL system, but you'll have to register in order to get it.

End of Year Offerings

Finally, Facebook and Google+ both announced they would offer users an end-of-the-year highlight function of one sort or another.

For Facebook, which offered its users "the year in a snapshot" function last year, the company is switching it up by allowing users to see their friends' year-in-a-nutshell highlights as well. These include top stories, best comments, relationship status updates, uploaded photos, and other major events in friends' lives, so if you did something big this year, your friends might be reminded of it soon.

Meanwhile, Google+ is enabling a new feature in its "AutoAwesome" automatic video and photo-editing feature, which will automatically generate a Year in Review retrospective video for some users. Google will be turning that feature on for only users who uploaded lots of photos and media throughout the year, so it's a bonus only for those who are either diligent Google+ fans or have enabled auto-upload on their smartphones.