I like the idea. If I'm playing with some facebook data, right now I use whatever language I'm confortable with and use its HTTP request functionality, and than manipulate the data how I want in that language. To achieve the same thing in pigshell I have to write a shell script that manipulates the data. What can pigshell do that I can't just do in another language?
In theory, the availability of APIs should be enough for the technical user to write their own data extraction routines, connect them to other APIs and so on, using their preferred language and toolchain. In practice, reading up the documentation, writing and debugging code sets up enough of a barrier to entry that it discourages casual usage without a powerful incentive.
The availability of a file abstraction covering many popular cloud services, web resources etc. enables casual, low cost experimentation across these domains, without having to read up each one of the APIs. If something clicks, then it may make sense to write a better "native" implementation.
