Measuring the success of Messenger Rooms involves several key metrics. First and foremost, we need to look at user engagement. This includes the number of users who have created Messenger Rooms, the frequency with which they use the feature, and the duration of their sessions. Another important metric is user satisfaction. We can measure this through surveys and feedback mechanisms built into the feature. By understanding how users feel about Messenger Rooms and what they like or dislike, we can make adjustments to improve the user experience and increase overall satisfaction. We also need to consider the impact of Messenger Rooms on Facebook's business goals. This includes factors such as the number of users who are retained or attracted by the feature, the amount of time they spend on the platform, and the potential for monetization through advertising or other means. Ultimately, the success of Messenger Rooms will depend on a combination of these factors and others that may emerge as the feature is used more widely. As a product manager, my job would be to continuously monitor and analyze these metrics and make data-driven decisions to optimize the feature and drive its success.