1) we want to have a very large validation community, ideally several thousand when mature
2) an individual can delegate (hence, DPoS) to a Validator
3) depending on the number of individuals that participate in the next few weeks we’ll have a better idea of the number of validators (a great case would be to start with people whose addresses have locked more than 5ETH)
4) In addition, we will also take into those that have been running a validator on the test-net. This experience will also be taken into account.
We are working on a blog post in the near future that will provide additional details.