I decided to stretch my brain this semester by doing all the programming and scratchwork for the course I'm taking in Ruby.
in reply to Score: Perl 1, Ruby 0
My main disappointments in Ruby so far have been the lack of autovivification in multi-dimensional arrays (doing dynamic programming without it is a PITA) and the available documentation not meeting my expectations.
I've subscribed to the "Ruby" tag in del.icio.us, but the S/N is swamped by Rails hype. Ruby does make me appreciate the "Huffman coding" of Perl. Haven't bothered with threads so far as they're not necessary to the problem domain.