Something strange is afoot. Probably temporary:
A post simply vanished. I re-entered it, and then there were two. I tried to delete one, and got a message "Delete error", and when I bring up the blog, both are now missing.
Also, in the dashboard, the list of recent activity (the left column) is simply missing.
Something going on there?
Of course, the Publish button problem is still with us: sometimes it publishes, sometimes it saves, sometimes it does both.