New projects only. Actually, the sort of projects Ruby will be used for are ones we don't actually do ourselves at the moment, because a 3rd party will come in and offer to do it in PHP or Ruby for much cheaper than we can. Historically they were done in Perl, but it's not a simple case of Ruby replacing Perl.
Still, the reasons why Perl is not an option are kind of interesting. As I said, I think there are some perceived (though not necessarily true) deficiencies with Perl, coupled with the feeling that Perl programmers are expensive and hard to find, while Ruby programmers (and especially consultancies), are cheaper, easier to find, and likely to continue to be in the future.
This would be far less notable if it were confined to just my company, but I think it's a growing feeling across the industry, at least in London.
