At the time of this writing, Drupal 8 is roughly a year and a half old. 8.3 is due in 30 days or so.
Looking back on Drupal 7 and it's infancy, we are at a pivotal point in Drupal 8 where contributed modules are maturing and offering new functionality that developers have been waiting for. It seems that a year and a half to two years is where things happen on a daily basis and options become available much more readily. What I find interesting is where some contributed modules will lag behind others maturity wise, but will have similar or near identical functionality to others. A great example of this for me is a situation where I needed to register users of different types. The idea is that with user types, they do not share all the same fields. So I needed a set of fields for user type 1 and another set of fields for user type 2. In Drupal 7 this was handled nicely with the Profile2 module and Profile2 Pages for allowing separate paths for each type of user to register on.