I don’t think the Mill would be significantly *better* than a GPU at what a GPU is good for, but with a goodly number of FP functional units, I think the Mill could be more or less *equal* to a GPU at what a GPU does. At least a mid-range GPU.
Where this becomes interesting is in situations where you don’t want to spend the power and cost budget for specialized GPUs- think tablets, smart phones, and net books. Here, havng a CPU that can do “triple duty”- have the power/cost of an embedded CPU, desktop CPU performance on general purpose workloads, *and* a decent GPU as needed, and you’ve got something *very* interesting. NVidia might not be afraid of the Mill, but ARM should be freaking paranoid.