Here is the fix for the recent Google changes to their pagerank API. For example, in the List Rank Dashboard Widget Wordpress Plugin (Version 1.7), in this plugin file:
list-rank-dashboard-widget/wp-list-rank-class.php
in this function:
function getGooglePR($url)
Change this line:
$remote_url = "http://toolbarqueries.google.com/search?client=navclient-auto&ch=";
to this:
$remote_url="http://toolbarqueries.google.com/tbr?client=navclient-auto&ch=";
And it works again... it's that simple!