It has been many months (back in December 2013, to be exact) since the last Google Toolbar Pagerank update. While at one point it may have been a more used and popular feature, it seems that now the Toolbar Pagerank is most often discussed because of its dwindling importance. The toolbar must be downloaded and installed, and the intention is for it to help provide users with the overall value (PageRank) of a particular site that they are on. One important reason that this tool has become relied on much less is due to the fact that it is only updated every few months; your official internal pagerank may differ (especially for new sites) from that of the snapshot that Google allows you to see via the toolbar.
So, how do we know that this toolbar is more than likely set to fade away? In a recent Webmaster Hangout, John Mueller of Google stated that going forward, they probably will not be updating it. When those words come directly from a Google representative, it seems fair to assume that their focus, updates and strategies moving forward will be elsewhere.