Twitter users will soon be seeing Promoted Tweets inside their timeline.
The rollout will occurr over the next few weeks. Promoted Tweets will appear only from accounts you follow. They will sit at the top until you see them, and then they will get pushed down by others' tweets like normal tweets do. They can also be removed from a timeline with a single click.
Critics will of course say this is invasive and blah blah blah, but really, the real-time microblogging network has taken a lot of steps to make this feature as unobstrusive as possible. I mean, if you're following the account, shouldn't you want to see their tweets anyway? A promoted tweet should be more relevant than the account's regular tweets, if anything. In which case, promoted tweets sitting on your timeline would actually be a value-add.
If Twitter had decided to push all Promoted Tweets into your timeline and keep them and the top and make them unremovable—okay, now you're pushing the wrong buttons. But by the sounds of the system they intend to implement, there shouldn't be any problems at all.