I am constantly learning new tools, even old fashioned ones, because I like to use the right solution for the problem.
Nevertheless, I wonder if there is still any reason to learn some of them. awk for example is interesting to me, but for simple text processing, I can use grep, cut, sed, etc. while for complex ones, I'll go for Python.
Now I don't mean that's it's not a powerful and handy tool. But since it takes time and energy to learn a new tool, is it worth it ?
I think it depends on the environment you find yourself in. If you are a *nix person, then knowing awk is a Good Thing. The only other scripting environment that can be found on virtually every *nix is sh. So while grep, sed, etc can surely replace awk on a modern mainstream linux distro, when you move to more exotic systems, knowing a little awk is going to be Real Handy.
awk can also be used for more than just text processing. For example one of my supervisors writes astronomy code in awk - that is how utterly old school and awesome he is. Back in his days, it was the best tool for the job... and now even though his students like me use python and what not, he sticks to what he knows and works well.
In closing, there is a lot of old code kicking around the world, knowing a little awk isn't going to hurt. It will also make you better *nix person :-)