According to http://developers.facebook.com/docs/reference/plugins/like/
I change the open graph tag to <meta property="og:site_name" content="abcdefg1234"> from <meta property="og:site_name" content="testupgrade"> , but i doesn’t take any effect.
Anyone have any idea?
This may be caused by the caching Facebook uses, you can use the Debugger to see what the Facebook bot is seeing and to refresh the cache for your URL