Twitter is rolling out Twitter Surveys, a new brand-research tool that lets marketers create in-tweet mini-surveys of between one and five questions. The surveys can be targeted to users based on whether they've previously received Promoted Tweets from the brand, and are expected to have an engagement rate of between 1% and 3%. "There's been [an issue] in the industry for brand research when it comes to low response rates. ... This solves a big problem," says revenue chief Adam Bain.