Could it be related to a Log4j issue?
132 karma · joined April 20, 2015
If you don't need to support very old browsers you can easy go without jQuery.
Have a look at http://youmightnotneedjquery.com
I think there are many reasons for the productivity boost. Thinking in components, more readable code, great debugging possibilities, understandable data flow, to name a few.
And, last but not least, it is lots of fun :-).
We use React since four months, and we develop faster compared to before, when we used only jQuery.