No official announcement has been made (yet) about the "recommended for you" feature that will gradually roll out for all users according to TechCrunch.
These recommended posts are essentially your discover page curated into your feed and will be carefully selected for you by Instagram's algorithms in hopes that each image will pique your interest and prompt you to follow whoever took it. This is all in the big plan that Instagram has to make users follow more users.
"These posts are suggested based on posts liked by accounts you follow," Instagram explains.
This change for Instagram is a fairly big one and could effect how users perceive the platform, although, Instagram hopes that the shake up will generate more engagement and followership from their users.
Recommended posts might change the way users start to interact with content on their feeds. However, users may start to be disinclined to hit 'like' on anything on their feed now that they feel their carefully curated feed has been compromised.
Businessinsider also mentions that these recommended posts could deter users who prefer separate feeds which in turn could push those users away to other competing apps such as Snapchat.
What does this mean for brands? It's too soon to say, however, brands should focus even more on creative content appropriate for Instagram to stay relevant and take the next months 'likes' with a grain of salt because each new Instagram shake up will have an affect on engagement.
What does this mean for you? Well I'm not sure, but for me I will probably see an influx of puppies and yoga posts on my feed. Not really complaining about that.