MetaX Weekly AI Paper Review Week 24 2025 -- From Reinforcement Learning That Trains Like a Game to Development of Ultra-Small High-Performance Language Models Running on Smartphones, Diverse Domain Expansion of Multimodal AI Models and Development of Video and 3D Generation Models: Reinforcement Pre-Training trains next-word prediction of LLMs like a rewarded game to improve performance -- a new training approach. Will It Still Be True Tomorrow research distinguishes whether LLM answers will remain valid over time (evergreen quality), reducing incorrect information generation and improving reliability. Lingshu paper develops medically specialized multimodal AI that understands and reasons with medical images and text together, showing superior performance to existing models. Confidence Is All You Need research develops technology where AI self-evaluates the reliability of its own answers without expensive labeled data -- enabling uncertainty-aware responses. Additional papers covered: ultra-small language models optimized for on-device inference on smartphones; multimodal AI extensions to new domains including audio and video; 3D generation model advances enabling creation of 3D objects from text or image inputs; and video generation improvements for temporal consistency and motion quality.