The introduction of the discussions feature on GitHub provides a new, dedicated space for collaborative communication within open-source software (OSS) projects. This paper investigates the impact of discussions on community engagement, focusing on newcomer onboarding and the activity surrounding issues and pull requests. Through a comprehensive empirical analysis of 285 OSS projects, we observe a significant shift in participation patterns, with discussions emerging as a more attractive entry point for newcomers compared to traditional mechanisms like issues and pull requests. Our findings suggest that while discussions lower the barrier for newcomer participation, it leads to a decrease in traditional contributions such as new issues and pull requests. Additionally, we explore the engagement levels of different contributor roles, demonstrating how discussions foster diverse interactions and community involvement. The results provide critical insights into the evolving nature of collaboration on GitHub and highlight the role of discussions in shaping the dynamics of OSS project ecosystems.