Apache Lucene™ 5.0.0 is coming! by Michael McCandless.
At long last, after a strong series of 4.x feature releases, most recently 4.10.2, we are finally working towards another major Apache Lucene release!
There are no promises for the exact timing (it’s done when it’s done!), but we already have a volunteer release manager (thank you Anshum!).
A major release in Lucene means all deprecated APIs (as of 4.10.x) are dropped, support for 3.x indices is removed while the numerous 4.x index formats are still supported for index backwards compatibility, and the 4.10.x branch becomes our bug-fix only release series (no new features, no API changes).
5.0.0 already contains a number of exciting changes, which I describe below, and they are still rolling in with ongoing active development.
…
Michael has a great list and explanation of changes you will be seeing in Lucene 5.0.0. Pick your favorite(s) to follow and/or contribute to the next release.