Before you get the board, you have to agree to a number of terms from Google. Because there is a limited number of boards, Google wants to know precisely how you plan on using it. The boards are necessary because developers need to make sure that their modules work with the circuitry of the handset.
The first set of boards is expected to ship later this month. If you do receive your dev board so soon, it means that Google likes your idea and thinks your module has merit. By the way, the next developer conference will be taking place in November. By then, we will know who won the $100,000 for the first Project Ara Developer Prize Challenge. You need to send in a 5 minute video along with the official entry form. The entry must be in Google's hands by September 1st while a working module must be received by September 30th. On that date, the winner will be notified. The first place winner receives $100,000 and the knowledge that his module will certainly be offered to Project Ara buyers.
Google is releasing a developer board for those developing modules for the Project Ara modular phone