hmm...dual licensing should really have been clearly advertized, together with corresponding commercial pricing. Most enterprise customers won't evaluate products that are on AGPL only, even for internal needs.
My understanding would have been that AGPL means all code that interfaces with the database (i.e. all code that uses ReQL) must also be AGPL. That would have instantly disqualified RethinkDB for me (whether the understanding is right or not) and I'm sure I'm not the only one to think that way.
Considering even GPL-licensed software often prominently advertises commercial dual-licensing, this seems like a major oversight (if it wasn't for ideological reasons).
The client drivers are licensed separately under the Apache license. Only the database server itself is AGPL. Read the last question on the rethinkdb.com FAQ: https://rethinkdb.com/faq/