Moving from Fast to Solr
Posted: | More posts about Lucene Solr Free Software fast
Sesat has published a nice in-depth report on why to move from Fast to Solr. The article also includes a description of the steps taken to move over as well as several statistics:
On a related topic, the following article details, where Apple is using Lucene/Solr to power it's search. Spoiler: Look at Spotlight, their desktop search, as well as on the iTunes search with about 800 QPS.
Update: As the site above could not be reached for quite some time, you should either look into the Google Cache version.