Translation memory systems

[Warren Block]

Several PO/gettext translation systems offer translation memory, 
avoiding the need to retranslate strings that have already been 
translated.

Open Source
Pootle (http://pootle.translatehouse.org/)
Weblate (http://weblate.org/en/)

Commercial
Transifex (https://www.transifex.com/)


PC-BSD uses Pootle to translate their documents, but as far as I know, 
they use MediaWiki and not DocBook.

Does anyone have experience with any of these systems?