Gadget-BugStatusUpdate.js needs to be adapted to work with Phabricator. Currently, the gadget queries Bugzilla's API dynamically to show the wiki user the updated status. The goal is to do the same with Phabricator's API, Conduit.
There is already some discussion at http://en.wikipedia.org/wiki/MediaWiki_talk:Gadget-BugStatusUpdate.js#Adapting_this_gadget_to_Phabricator
It looks like maniphest.info should provide the needed information.
However, from talking to people on the phabricator IRC channel, it does not seem that Conduit supports JSONP or CORS. However, if not, we can look into alternatives, like a single-purpose proxy (e.g. a JSONP proxy on Wikimedia Labs) or configuring the server to support CORS.