How up to date is JavaScript framework?

I often visit dofactory and have been tempted to purchase the JavaScript framework since late 2013.  But as it was getting closer to 2014 I decided to hold off thinking a new version would become available.  Now, it's 2015 and I really want to learn advanced topics but concerned the material is now out of date by almost 2 years.  Can someone (even if it's biased from dofactory) provide me with some information?  And, in that reply I'd like to know what version of jQuery they're using in their topics in this area.