From the reader's perspective:
Chapter titles do seem to be out of fashion, at least in adult fiction. I just took a moment to search my bookshelf for any novels that use chapter titles, coming up with none (though I only searched the fantasy and scifi section) for adults, but two series for YA (Harry Potter and The Spook Series).
A good chapter title can raise the reader's expectations and, after reading the chapter, add to his or her understanding of what was the most important thing that happened in the chapter. If you choose the title well, you won't give away too much of the plot.
From the writer's perspective:
I use them in my own writing. A good chapter title is hard to find, but the search alone (as well as the title once you've found it) helps you, the writer, focus and bring out what you really want to achieve with this chapter. Often enough, as I am struggling to come up with the appropriate title, I realize what the chapter is about, and it affects the plot. (Other writers might achieve the same effect with meticulous outlining, but that doesn't work for me.)
To me, chapter titles are part of the story, not separate from it (like a newspaper heading.) They should add to the story. If you string all your chapter titles together, you should have a near-complete list of all your major plot points.
So my advice would be: if you like them, use them. I wouldn't consider them a waste of time and effort even if, should your novel be published, the editor wants to omit them. They are really a great tool to help you organize your story.