@clueax You mean like a restaurant chain, a clothing company, or auto dealer? Probably like Usenet you're more likely to see, at least at first user-driven interest groups (lists/hashtags) instead.
Other than to @ them for a complaint or compliment I'm not sure what the incentive is for them or the community. Many users are surely going to reject any outright marketing. Even most of the news and tech orgs here are largely driven by their individuals rather than the brand.