Core i7 and 16GB RAM is what we tested on. It's a reasonably sized machine for a sophisticated developer. (And only sophisticated developers should be playing with pre-release software.)
I don't know if it would run on less because we didn't try. I wrote that because I know it WILL run on that, and I don't know if it will run on less. I upgraded from 8 to 16 GB before I even tried.
If you find you can get by with 8 GB or 12 GB, or a smaller CPU, please share it on the developer channel, or let me know and I'll post it.
That's really bad. You didn't test on more than one machine?
Silly person. We tested on a lot of machines. They all were reasonably sized.