It appears Google's(s goog) ambitious modular phone experiment is moving into the next phase. At Google's I/O developer conference, Google's Advanced Technology and Projects team was able to boot a Project Ara device in public for the first time, and now it seems that the project has announced the first 100 members of the public to get a prototype.
When Project Ara was announced in October 2013, Google's (then Motorola's) ATAP team invited users to join a program it called "Ara Scouts," which recruited volunteers from the public to complete challenges through an app called Dscout. Most of the "missions" centered around how phones are used in daily life, for example, "Mission 6: Stuff I Always Carry Around." According to the announcement page, the one-hundred users who will get a prototype device for free were selected based on their performance and activity in the Dscout program. However, it is unclear when those lucky Ara Scouts will be receiving their prototype devices. I've asked Google for more information and will update if they get back to me.
The announcement also marks the end of the Ara Scouts program in its current form. In a farewell email to Ara Scouts obtained by Alex Hernandez at Techaeris, outgoing ATAP Design VP Dan Makowski writes:
After 9 missions with participation from over 30K people across 111 countries, we're bringing the Ara Scouts program to a close. As many of you may have seen at our recent Google I/O presentation, the team's focus over the next 8 months will be to bring our functional prototype into reality. We'll be reaching out to our 100 most active Ara Scouts soon, letting them know that they'll be among the first to get an Ara phone outside our team. You can see a list of the recipients right here! And the other 29,900 of you – don't worry 
– you'll be seeing more from us as we get closer to launch.
These changes come as Makowski is leaving Google for a post at Capital One, as mentioned in the Ara Scouts farewell email and a post on his personal blog. The ATAP team has started other ambitious projects, such as its 3D-scanning tablet, Project Tango, which is also aiming for a commercial launch next year.
Amongst the excitement that Project Ara seems to be moving full steam ahead, it does look like Google is controlling expectations: At the Project Ara developer's conference in April, project head Paul Eremenko said they will launch a Project Ara device in January 2015, but the "eight month" number Makowski noted corresponds to a launch date in March at this point. Considering the difficulty of a project like Project Ara, and the fact the ATAP team had trouble getting its prototype to boot at I/O, it might not be the last time we see its launch date pushed back.