Hey! Its hard to say at the moment. The official line is still 1.5 I believe. Just learn to use it using Components instead Directives so it will be easier to jump to Angular 2.
I'm sure there's a bunch of people already working with Angular 2 who would say otherwise, and to be honest I haven't had a bunch of time to play with 2 either :)
Thanks so much for that link and your reply! I am reading the article on Components now; very interesting so far!