Google has officially deprecated their AdSense plugin for WordPress this month. It is no longer available for new publishers to sign up for. So if you want to use it on a new blog or you are new to AdSense, you need to find a different plugin.
On April 5, 2017 existing publishers will not be able to change their ad settings or ad units through the plugin. Then on May 3, 2017 Google will no longer provide support for the plugin.
Google said "We frequently review our products and features to ensure they're providing maximum value to our users. After reviewing the AdSense Plugin for WordPress, we've decided that going forward we can better support WordPress publishers through new innovative features like our automatic ad formats and other upcoming initiatives."
Here are the "key dates" which I already summarized above:
- Early March, 2017: New publishers will not be able to sign up for AdSense by using the plugin.
- Early April, 2017: Existing publishers will not be able to change their ad settings or ad units through the plugin.
- Early May, 2017: Google will no longer provide support for the plugin.
For more details see this Google help page.
Forum discussion at WebmasterWorld.