I’ve just found this wordpress plugin from Alexander Tumanov which permits to visualize your hosted panos.
Let test it there for some still pictures of mines:
Well, it seems to do its job but no zoom on your view,
nor heading choice (while mine have xmp photosphere datas);
No problem in full screen ; but forget to put hotspots ;
Nevertheless it’s an « easy install » nice plugin for simple cases.
To compare with direct google services you can go on my google+ page :