Group 1 - The core point of the article is that Meituan has officially released and open-sourced its large model, LongCat-Flash-Chat, marking its first foray into open-source AI models [1] - LongCat-Flash utilizes an innovative Mixture-of-Experts (MoE) architecture with a total of 560 billion parameters, and activated parameters ranging from 18.6 billion to 31.3 billion, averaging 27 billion, achieving dual optimization in computational efficiency and performance [1] - The Longcat AI conversational application for end-users is now available on the web, with a mobile version yet to be launched; the web version currently supports online search and features a "deep thinking" option that is still in development [1]