Added Dec 2013. re: 'internal architecture/design for hackers'.
If you last looked more than 18 months ago, I'd say the doc situation has significantly improved. There isn't a complete manual by any means, but perhaps what is now in place is enough to get some folk up to speed.
New since summer 2012 or thereabouts:
Of course, some doc related projects started more than a year ago have been further developed. Most notably, Larry Wall, with help from a few others, has pushed the count of Perl 6 Rosettacode entries to around 600.
(Talking of Larry, he has said he is working toward publishing an O'Reilly book, a Perl 6 equivalent of the Perl 5 "bible" Programming Perl.)
With all that said, a word of caution. If by "user" you mean relying on Perl 6 the way someone might rely on Perl 5, things are far, far from that. Perl 6 won't be able to support users and doesn't need contributors in the way that Perl 5 supports users and needs contributors; Perl 6 can only support users willing to work with it despite its many weaknesses and relatively high rate of change from release to release.
In reply to Perl 6 documentation (Re^2: To monks who are interested in contributing to Perl 6 but are not now doing so. What is stopping you?)
in thread To monks who are interested in contributing to Perl 6 but are not now doing so. What is stopping you? by raiph