For the node specs, ZooBC are doing the first internal stress testing now, and will use that to determine a good trade off between TX/second and hardware specs that will be affordable for average people. We will publish some numbers as soon as we have them.
The higher we make the minimum specs, the more TX/sec we can safely allow, but also the more it becomes centralized to rich people. So we are working to find the balance.
Rule of thumb, I want our minimum specs to be about what you'd get for $50/month with a VPS.