I recall it being around 77%. Do a search and you'll find some information that was posted by DesiDentist a couple of years ago. You can also look on the WREB website.
If you go on the wreb website and read the newsletters, i think the last one for last year had some stats on the passing rate.
with the new format i think the only difference is that once you get a grade below 75 in any section, you will have to retake that section, even if your final score is 75% or higher.