The time has come. Apocalypse. (Not really.)

Twitter announced Thursday something many of us had been expecting for awhile: users will now start seeing Promoted Tweets in their timelines. It’s simple. A brand pays Twitter for extra exposure and followers of that brand will see the Promoted Tweet at or near the top of their timelines.

The new feature is being cast by Twitter as a way for users to be assured that they never miss the most important tweets, like special offers, deals or news from organizations they follow.

According to a company blog post:

We all come to Twitter to connect with the latest information on the topics and people we care about. So when we decide to follow a favorite brand, business or charitable organization, we expect to be among the first to get a special announcement, access to exclusive content or a great offer.

While some users may indeed enjoy the new feature, it’s clear that this is less about improving product and more about monetizing the platform. All of Twitter’s former Promoted Products allowed brands and businesses to pay for special visibility, either in search results, trending topics or “Who to follow” suggestions in the sidebar.

With today’s new feature, however, those same brands can finally pay for extra visibility in users’ timelines, probably the most valuable space on Twitter. Thankfully, Twitter isn’t just injecting tweets in just any stream: you must be following the company to see their promoted tweet.

Twitter says the new feature will roll out over the next several weeks with a select group of partners, including the following:

Best Western
Dell
Gatorade
Groupon
HBO
JetBlue
LivingSocial
Microsoft Xbox
Red Bull
Sephora
Starbucks
Summit Entertainment’s “50/50”
TNT
Virgin America

non-profits
charity: water
Make-A-Wish Foundation
Room to Read
The American Red Cross
Water.org