I did have a short look at the tutorial, but I had a bit of a hard time diffing it mentally, as I am still fairly new to Lisp. But I will definitely point him in that direction if he is interested in having more than a cursory glance.
It's hard to say. I think most people might be discovering arc and never coming to the forums or our community frontpage: http://arclanguage.github.io. They're probably still using arc 3.1.
I prefer anarki because Arc 3.1 has been around for five years without updates, and we've found some serious bugs in it, and also made some serious improvements (tests, online help).
