Still very active everywhere I've played.
I am playing in Europe for about 12 months, and while the game is still going on, the number of players doesn't increase...some are joining, and about the equal amount leaves. So I wonder if the game had its peak already. After a few months it becomes kind of repetitive... but anyway, it's a good game, I enjoy playing it, especially if I come to some new city.
I realize churn is a common occurrence with any MMO, but Ingress always seemed like more than a game; our group socializes outside of the game and I wouldn't be surprised if we all remained in contact long after Niantic shuts it down.