http://feather.perl6.nl/syn (contains the Synopses: the official Perl 6 specification, which supersedes the apocalypses and exegeses, and which is bundled with Perl 6 builds. The rapidly growing Perl 6 test base is another {very important, complementary, and emerging} part of the Perl 6 specification as well.)
Australian Perl 6 Wiki (For a long time, the Perl 6 Wiki at perl.net.au was the best general introduction to Perl 6, and was a great point of departure to other Perl 6 resources around the web. It's still worth checking out.)
Perl 6 Users FAQ (The initial large batch of text and links on this Wiki originally came from this FAQ. The folks there deserve much thanks for "Wikifying" my original ugly ASCII Perl 6 Users FAQ, which was compiled for the inaguration of perl.perl6.users.)
Most of the information on getting started can be found on this getting started page. You may also find the following links useful:
State of the Onion (Larry Wall's yearly Perl status reports, with much humor-infested commentary on Perl 6 design philosophy, processes, and illuminating insights.)