I'm very excited. Within minutes of discovering the release, I signed up for an invitation to try it out. I'm eagerly awaiting the day when I get the chance to try it out for myself.
I see this move as having both benefits and drawbacks.
Until Google Classroom is released for all Google Apps for Education domains, I don't think it will gain a strong foothold. I've seen tools and technology unused or under-used because of the unavailability or poor quality of instruction available to educators. As a community who plans ahead, educators will likely take some time to get a feel for how the tools work before jumping in with both feet. And that's a good thing; we are tasked with developing learning environments that support and extend student understanding and nurtures curiosity. Frustration with new tools that don't work as expected can be more damaging than holding off until the tools are understood.
I'm an early adopter. I've always been enthusiastic to try out the newest toys, experiment with (and sometimes on) my class, and to learn from mistakes as I make them. I'm currently working on scripts that will tie Google Drive and Google Sites more closely, since I saw a need and felt that I could and should address it.
So within the new ecosystem of Google Classroom, where is the room for educator-innovators? In the Google+ Community for Apps Scripts for Education - Builders and Users, +Andrew Stillman asked the following question: "How can Google, the non-profit orgs, districts, and teachers combine efforts to ensure this sharing can continue and be well-enough rewarded so that we can attract and retain talented contributors to this alternate model to the edtech startup incubator?"
I'm extremely curious to see what the future holds. There are currently 2 880 members in the G+ Community (at the time of writing), and I'm confident many of them are curious, too.