This is good for some and not for others.

For me its great because I can continue with 100% bonus miles for a few months before i use status match at Delta. feel united ROYALLY SCREWED all elites except for 1Ks. Because of the 50% REDUCTION in bonus miles I am going to Delta and their status match.

The thing iI still do not understand is this:

The CO gold ( 50 k miles) get 100% bouus miles
The UA Premiere exec ( again 50K Miles) get 100% bonus miles.

Therefore there is no need to make any compromises since they both the same. BUT UA decided to reduce the benefits by a whopping 50% as a random act of screwing.