This week in social media, the blame for your Facebook bubble was officially placed on... you. Meanwhile, Twitter bolstered its marketing team, Snapchat debuted new video ads, Pinterest raised $186 million in funding, and Meerkat cozied up to Facebook.

It's time for Social Media Sunday!

Facebook:

Your News Bubble Is Your Fault

Many media analysts worry that the algorithm-powered way most American get their news on sites like Facebook leads to a "bubble" -- where users eventually only see news and perspectives that they agree with.

It's a problem if you believe the capital-T Truth can only be reached by challenging your own viewpoint. But that's your problem, because it's your fault, says Facebook.

After studying millions of its most political users, Facebook released a research report in the journal Science this week officially placing the blame for myopic news feeds not on its algorithms, but on users' choices.

"In the end, we find individual choices, both in terms of who they choose to be friends with and what they select, matters more than the effect of algorithmic sorting," said Facebook data scientist and the study's co-author, Eytan Bakshy.

In fact, the study found that Facebook's algorithm only makes a less-than 1 percent difference in reducing content with opposing viewpoints. Most of the ideological filtering happened at the point of friendship, with users tending to make connections with people who shared the same political viewpoint in the first place.

New App Install Ads, And New Ways to Block

On the business side, Facebook introduced a new tool for direct marketers to advertise apps -- while also introducing a tool for users to block app invites.

The new app install ad system incorporates open, cross-platform standards for deep linking apps, which according to TechCrunch, could increase Facebook's already gangbusters ad revenues by making it easier for marketers to get users from the point of seeing the ad all the way to downloading and installing it.

On the other hand, Facebook added a new option to the Settings page of its web platform called "Block App Invites" to help users remove annoying spam from friends who are entirely too interested in getting you to join them on Candy Crush Saga.

Twitter:

More Help at the Top for Marketing

As we reported in last week's Social Media Sunday, Twitter has been underperforming on Wall Street so consistently that it's nearing a crossroads for its very survival.

This week, Twitter took one step in bolstering its wimpy revenues by adding a new job to Twitter CFO Anthony Noto, according to The Wall Street Journal.

Noto will now head up the marketing team for Twitter at a time when the company needs to start producing. Noto has a track record of bolstering Twitter's position in the online world, as he was the point man on the company's recent deal to incorporate tweets into Google search results.

Meerkat:

Heading Facebook's Way?

Speaking of short-sighted Twitter, the social network has caused plenty of headaches for live-streaming phenom (and Twitter-owned Periscope rival) Meerkat, denying the app access to its data streams and generally trying to downplay the app as much as possible.

That may not have to put Meerkat down for good, but it seems like it was at least enough to push it away -- and toward Facebook. According to Digital Trends, rumors are circling that Facebook may be interested in acquiring Meerkat just as the live-streaming service announced an update to introduce support for Facebook accounts, along with a release soon of a developer platform.

Snapchat:

Introducing Ten Second Ads, at Two Cents Per View

Snapchat just got serious about its Discover platform for publishers. At the Daily Mail NewsFronts event this week, Snapchat unveiled 10-second ads for media companies, brands, and publishers that cost only two cents per view, according to AdWeek.

The program is appropriately called Two Pennies, and it represents a huge drop in price for advertising on the Snapchat Discover network, which launched in January at a price of 15 cents per view. This "change" means Snapchatters are likely to see more sponsored content from media outlets, and it means Snapchat's Discover platform may revitalize after months of stagnation.

Pinterest:

$186 Million in New Funding Round

It may not be the biggest funding round Pinterest's has ever had, but an additional $186 million in the image-sharing social media startup can't hut. According to Re/Code, the Series G funding round leaves Pinterest with a total of $553 million, and it's now letting its employees sell some of their shares in the company.

Normally at startups, employees are required to purchase their stock options within three months after they quit the company, which can be expensive (and is a way to boost employee retention).

But Pinterest isn't worried about losing staff. "We're trying to build this opt-in culture, and we think this is the way to do it," Sharp said to Re/Code. "People want to work at a company that has their best interest in mind."