You get a 404 when choosing 'New Post' from the quick create menu. I would either expect

• 'New Post' not to be listed at all (though it would be confusing seeing 'New Blog' there without 'New Post' which is the much more common action)
• It to open a form where you can choose the blog you wish to post to

Tested on current stable:

phabricator 25eea83bc05f17fb5f928f5bfbb4c746eecd1998 (Tue, Sep 20)
arcanist 10e5194752901959507223c01e0878e6b8312cc5 (Sat, Aug 27)
phutil fc84916a1a31865f8b48d99d98766b2a1c29ef3a (Sun, Sep 18)

Also a problem on this instance currently.