Google has just updated their API to query a websites pagerank through third party software like web services and browser plugins. I was quite surprised when all my hosted sites suddenly appeared with a pagerank of 0.
To calm everybody down, it’s not true It’s just that right now the plugins and web services can’t access the new way of getting the data yet. As soon as the developers of the plugin you’re using or the analytic service of your choice have updated the responsible code, everything will be back to normal. Nothing has changed with the pagerank itself, just the way software can access it.
For more information: http://searchengineland.com/oh-no-what-happened-to-my-pagerank-95929