Sources: Alexandr Wang said Me... Note
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Sources: Alexandr Wang said Meta's model currently in training, codenamed Watermelon, matches GPT-5.5 and uses an "order of magnitude more compute than Avocado" (Business Insider)

Business Insider: Sources: Alexandr Wang said Meta's model currently in training, codenamed Watermelon, matches GPT-5.5 and uses an “order of magnitude more compute than Avocado”  —  Meta is making significant progress in the AI model race, its superintelligence chief Alexandr Wang told employees today.