Grant Ingersoll, points out that Lucene in Action, 2nd edition is now available for early access. Read his post for a link to get 40% the early access edition.
The first edition was a venerable standby that is now quite dated, so I look forward to reading the new edition. I will have a review up soon.
In related news, Lucene 2.4.1 was released earlier this week. Lucene 2.4 was a major update released in October and 2.4.1 contains critical bug fixes.