Learn Apache Wicket, once you go Wicket, you'll never even think about Struts again....although, like COBOL, there are still a lot of legacy apps running on it.
Lately, I have been looking and Google Apps, Google Sites and Google Apps Script (which is basically JavaScript with some Google-specific APIs), at first I was skeptical, but you can do some pretty cool stuff with it.
That's another, learn JavaScript, and if you are doing front-end stuff, learn about JavaScript libraries, like JQuery.
I have to use struts for my job, it isn’t always what you want to do. I also have to build a hibernate app and I have no choice in the matter. I am the type that learns from necessity, if my job required skill A then I would obtain skill A. I also try to anticipate, if I think skill B would be useful on my job I will learn it on my own.