https://arstechnica.com/gadgets/2020/06/developers-leak-benchmarks-from-the-apple-silicon-mac-transition-kit/

As reported by MacRumors, eager Apple developers are already posting benchmarks on the developer transition kits for Macs with Apple silicon. These kits are based on the Mac mini chassis but include ARM-derived Apple silicon rather than Intel CPUs.

Before we dig in, it's important to note a few caveats. First, the CPU included in these developer kits may or may not reflect the CPUs included in future Apple Macs. These are not consumer products; they're developer tools. Second, the benchmarks were done using Rosetta, which likely still has many changes and optimizations coming. And thirdly, the developers who've leaked this information are in violation of non-disclosure agreements at Apple.