Well, commercial tweets anyway. Twitter is expanding its paid tweets program and will begin inserting commercial messages in your feed. So you'll be reading along and come across tweets from AMC Theaters, Xbox, American Express, HP, Disney, and others.

Twitter has an interesting explanation as to which tweets you'll be seeing:

A Promoted Tweet will appear in a user's timeline only if the Tweet is likely to be interesting and relevant to that user.

Our platform uses a variety of signals to determine which Promoted Tweets are relevant to users, including what a user chooses to follow, how they interact with a Tweet, what they retweet, and more.

Expect there to be a lot of grumbling about this from people who use Twitter constantly all day long and never pay one red cent for it.

Follow John Moe at @johnmoe