You can see the list of changes in the 5.6.1 release (both from the
5.005_03 release and the 5.6.0 release) by reading L<perl561delta>.
+=head1 Note about build and test times
+
+Note that the build times can vary considerably. Perl 5.8.0 is about
+twice the size of 5.6.1, and some source code files are quite large,
+so your compiler might have hard time processing them. On a fast
+modern system with lots of CPU and memory the build can be a matter
+of ten minutes, but on slower/older/more heavily loaded systems it
+can take up to eight hours, while half an hour to an hour being common.
+
+Also testing times vary a lot. Perl 5.8.0 has almost six times the
+the tests of Perl 5.6.1. Fifteen minutes to half an hour is quite
+normal, but a slow system may easily take an hour or more.
+
=head1 Highlights In 5.8.0
=over 4