It's here: https://meta.wikimedia.org/wiki/CentralNotice/Travel_Guide Not too easy to find at the moment. Don't know when it was announced, but it already has a fair number of translations.
2012/7/23 Eleri James elerijms@yahoo.co.uk
Where can we translate the central notice that has just appeared regarding the proposed WMF travel guide?
Eleri James
Translators-l mailing list Translators-l@lists.wikimedia.org https://lists.wikimedia.org/mailman/listinfo/translators-l