Many webmasters and SEOs are reporting seeing an issue with the PageRank distribution report in Google Webmaster Tools. If you login and click on crawl stats, and then scroll to the bottom, you may or may not see data. I personally do not see any data for this site. In fact, for me it reads:

JohnMu from Google confirmed the issue in a Google Webmaster Help thread saying:

Just another reason not to be freaked out and too concerned with the data shown in Google Webmaster Tools.

Forum discussion at Google Webmaster Help.