Meta just dropped SAM 3D, but more interestingly, they basically cracked the 3D data bottleneck that's been holding the field back for years. Manually creating or scanning 3D ground truth for the messy real world is basically impossible at scale. But what if you just have humans rank model outputs? Route the weird edge cases to actual 3D artists to model, loop it back in. Suddenly you can annotate like a million images. It's basically RLHF for 3D reconstruction. Synthetic data is pretraining, real world ranking is alignment. They borrowed the whole damn playbook and it actually works. Two models - one for objects/scenes, one for humans. They're already shipping it in FB Marketplace so you can see if that lamp or chair looks good in your room before buying. Also they're releasing everything - models, code, their human body rig under commercial license. And they built an eval set of actual messy real-world images to help bridge the sim-to-real gap. The data engine thing is the most interesting though. 3D has been bottlenecked by ground truth forever. If verification scales easier than creation, suddenly the whole game changes.