Simon Willnauer, the new PMC chair of the Apache Lucene project, recently presented at ApacheCon 2011 on the status of Lucene 4.0.
So when is Lucene 4.0 going to be finished? It could be a while or it could be in the next few months. Willnauer said he was wrong before in his predictions for a launch date so his current estimate is 3-12 months. A nice, safe prediction :)
Listen to his complete presentation on Lucene 4.0 here: