Last modified: 2013-06-13 17:26:41 UTC
en.wiktionary.org has a page for announcements which uses a pretty standard format which would work nicely as an RSS feed with a little wikitext parsing. The announcements page is not much used at the present but it's a good idea and making a feed for it could give it a little push.
http://en.wiktionary.org/wiki/Wiktionary:Announcements has not been used since 2010. :( Hence this is likely nothing anybody should spend time on currently, unfortunately.