It's hard to know exactly how big the scale is. I don't have any specific statistics, but I can give you my own perspective:

I haven't stopped using reddit, and probably will not stop using reddit. I am really really liking snapzu so far, and very well may make it my 'home page of the internet'; but reddit has a lot of irreplaceable things for me. The most prominent of them all, is a little subreddit named /r/exmormon. It is a subreddit designed for people in various stages of progression out of the Church of Jesus Christ of Latter Day Saints. It has become the forum for discussion on this kind of thing, surpassing even sites dedicated entirely to supporting these people. It has been extremely valuable in my life, and just 'stopping using it' probably isn't going to happen.

While a lot of subreddits can, will, and have transferred to snapzu seamlessly; not all of them are able to. While many people will be able to cut reddit off entirely, the AMAgeddon simply isn't enough for me to do so. It's changed the way I feel about reddit and its administrators, sure...but I haven't left it.

While I obviously wish the AMAgeddon never happened, I am happy that I've been able to come across snapzu. It's really something special. :)