Hi Joseph,
That's correct, pogoscript is written in pogoscript. There are one or two files that aren't yet, but that's more down to laziness than any technical limitations.
As for real world use, we have made good use of it in writing quite heavy front end browser apps with Angular JS (which is a beautiful thing by the way). One of them is for development purposes and the other has been live for some months and used by internal staff (20-30 users). Both apps are thousands of lines of code and make good use of the async operator to make AJAX calls - you really don't have to think about callbacks anymore, a very relaxing and productive programming experience.
For crawlers I think Node is a very good fit. One of my first node apps was a crawler and I was convinced when it performed 2-3 times faster than the equivalent asynchronous C# app. Pogoscript was motivated by that experience, especially the callback hell.
Cheers - Tim.