Something went wrong - -32300 : transport error - HTTP status code was not 200 wordpress
I received this the other day and discovered that disabling the Google XML Sitemap Generator resolved the problem. Something about it pinging sites was causing the error, and while the post was going live, it wasn't saving the tags for some reason.
I don't know if the error was on the plugin side or because the plugin couldn't notify the sites and that caused a problem, but I figured I should let someone know in case they're running into the same problem.
More information here: http://silverpenpub.net/technology/google-sitemaps-creates-error-on-wordpress