thanks for posting this question. I had not heard of it and therefore went to their web site and browsed.
One part of it I find quite intriguing. It seems a great site where activity-minded people can find each other and exchange ideas and post challenges. I am sure that has appeal and will help some people stay motivated. That is a plus.
As I further browsed I looked at some discussion forums and checked out wheat they had on strength training. As am example: A guy had posted a question about his shoulder that was hurting after bench pressing. The advice he got was – for the most part – what you would hear in the gym between buddies who may mean well but often do not know what they are talking about. That worried me and puts a minus there.
On balance, I hope that this will do more good than harm. If it gets 1000 people moving at the expense of one rotator cuff injury …… I guess it’s good.