I work at GeoCat bv (@geocat_bv)
WFS Filters based on WFS indexing with SOLR
Search engines: nojs, sitemap, schema.org,...
Several Harvesters fixes!!
CORS support and improved proxy
Events and listeners
Custom Metadata UUID
"Just created" flag
XSS security improvements
New languages!
Focus on 3.2.x (and 3.4.x - develop)
Improved workflow
Improve Scalability (Docker, SOLR)
SOLR support/Elastic Search
Better overriding of translations
Dashboard
Anything you want to contribute with :)