I finished the talk I was working on. The slides and video can be found at http://blog.timbunce.org/2008/03/08/perl-myths/

In the end I didn't include stats of other languages in the slides. I just quote the stats for Perl's own test suite over the last 5 years (slide 44):

2002: Perl 5.8.0 had 26,725 core tests, +41,666 more for bundled libraries etc.

2007: Perl 5.10.0 has 78,883 core tests, +109,427 more for bundled libraries etc.