Serving global content is easy to scale, since it's very easy to cache and easy to distribute across a cluster of computers. The real challenge comes when you have to serve and generate different content for different users and you can't use a global cache.
It sounds to me that they are serving global content - - and doing this, 1000 req. pr. sec is not that impressive and almost any framework tied to memcached could do this - - or even better, setup nginx to use the memcached module.
I don't think anybody is suggesting it's a miracle, or only possible with Catalyst. Just an interesting story of scaling a dynamic site using off-the-shelf Open Source components.
You could do this kind of serving in Ruby on Rails, Django or any other framework. Nothing really interesting, other than it's Catalyst - which for me does not make this any more interesting - - especially also since they use memcached caching to take down the load.
It sounds to me that they are serving global content - - and doing this, 1000 req. pr. sec is not that impressive and almost any framework tied to memcached could do this - - or even better, setup nginx to use the memcached module.