Twitter has been playing with this particular feature for some months now
Twitter has announced that it is now introducing a new type of ads that is based on web-surfing activity, much in the way Google or Facebook do, for instance.The program is called tailored audiences and has been rolled out on a smaller scale back in mid-summer. The tool can be used by advertisers to target users that have shown an online interest in the category that their brand falls into.
So, if you’re looking for a particular Christmas gift, for instance, you’re likely to get ads on Twitter from brands that sell that kind of item.
According to the blog post that announced the changes, beta user HubSpot noticed a 45 percent spike in engagement rates compared to the historical average, while Krossover’s cost per acquisition decreased by 74 percent.
As mentioned, Twitter isn’t the only one to take its hints from your browsing history as other companies have been doing it for far longer. Basically, if you regularly ignore ads, you’ll probably ignore these new ones too.
Also, the company has previously said that it will respect the "Do Not Track" option if enabled in the users' browser.