Why wouldn't it? While we've seen a trend towards consolidating systems infrastructure using more robust programming languages - as long as the shell is used for human-computer interaction (and I don't see this going anywhere), shell scripting will be around as a natural extension of the interaction. There is a beautiful ergonomics in conserving commands that you typed and interactively improved in a text file for future repeated execution.
I have bash and perl scripts that keep major business critical services running that are about that age. Why would I think scripts I write today won't still be running in 20 years time?
It occupies a sweet spot of being ubiquitous, quick to write/deploy and naturally interfaces with OS commands. It's the glue that holds unixes/linuxes together.
