Not trying to start a flame war or something on this list, just curious about the reasoning....
Why only Google+? We would love to test it but I refuse to get a Google account due to privacy and other civil liberty issues.
There's no risk of starting a flame war with me. I understand your point of view completely and sympathize.
For any other people reading who would like to avoid Google+, there is now also a Google group that I can invite you to (which I don't think requires Google+ membership). So if that works for you or anybody else, I would be more than happy to invite you.
So let me refresh my invitation to the beta test now and say that Google+ membership is no longer required.
If there are any questions why this is on Google Play, I can justify that as well.