These changes take the AWS SMS delivery from being suitable for ops alerts and the like, to being usable for end-user products.<p>On several projects where I've been involved, we'd have to justify why AWS could not be used, and why we needed a Twilio account instead, like the bad UX (non-customizable SNS opt-in messages) and US-only numbers. With these new capabilities, I think some non-trivial portion of AWS customers that are looking to add SMS messaging will pick this instead as the path of least resistance, even if Twilio is still more advanced.