The new features announced at MongoDB.local NYC 2023 include Atlas Vector Search, which allows users to store and search vectors alongside their business and transaction data, without the need for a separate database. This feature enables teams to deliver more relevant, context-aware results to end-users, including the possibility of expanding Large Language Models (LLMs) with proprietary data to improve accuracy and performance. Additionally, Atlas Stream Processing is being developed to enable event-driven applications, allowing developers to work with streaming data alongside their existing data in the database. The new features are designed to help teams create more efficient and scalable applications, while also improving the overall developer experience.