The pdf says "version: 9 September 2010". I haven't read it yet so can't comment on the content.
Nothing significant has changed in Perl since 5.8 so it is up to date enough. Perl 6 might be what you are referring to, but I doubt anyone is running perl 6 in production currently.
Our definitions of "significant" differ so much that I wrote Modern Perl to demonstrate precisely how to write great Perl with 5.10 and 5.12 instead of 5.8 and earlier. See http://www.onyxneon.com/books/modern_perl/
The author recommends at least 5.8 so that is a few years out.