The latest Development diary (the mini one) said they didn't have time and it is buggy so is locked currently and will be fixed for the first patch.
thats now on first patch thats not a hotfix for major issues. we are currently fixing those things you guys find now first before we return to out of syncs in hotjoin MP. Its working much better now though but not quite there yet.
here is the mini-dd did about it: http://forum.paradoxplaza.com/forum...Mini-Weekend-Dev-Diary-Hotjoining-Multiplayer