I upgraded Easy FancyBox from v126.96.36.199 to v1.5.0 and noticed my Youtube vids no longer were opening in overlay mode. I was using shortlinks similar to below with both Autodetect and Autodetect Short links settings checked. It used to then automatically populate the
"class="fancybox-youtube". But with upgrade it no longer does this. I worked around it by manually populating the class. But thought you could use the FYI.
Note: I did upgrade WordPress from v3.5.1 to v3.5.2 at the same time I had upgraded Easy Fancybox plugin.