Hi! I'm a reader of your blog, and I was hoping I could pose a question to you. My friends and I have been debating how to present italics in a manuscript. Some say underlining, but I recently heard that editors prefer straight-up italics, so they don't have to change the format later. Do you know which is currently preferred?
A lot of this depends on which software you use to create the manuscript and which software the publisher uses to typeset. Generally, if you use Microsoft Word, it doesn't matter how you indicate italics because it can be converted to usable files for most advanced typesetting programs with the styles intact. In this case, it's a simple Find/Replace for the typesetter to tag your styles in their program.
However, if you're using WordPerfect (and if you are, stop it right now and join the 21st century!) or some other archaic word processing program or if you've added a lot of unusual styling or fonts to your document (and if you have, knock it off!) that won't easily import to QuarkXPress or InDesign (the two most commonly used typesetting programs), the styles are stripped out in the conversion process and the typesetter must reference the original file to put the styles back in. In this case, underlining is MY preferred way to indicate italics because it's much easier for the typesetter to see them.
As to which you use, if the publisher's website doesn't state a preference, go ahead and use regular italics. If they want it underlined, they'll do it themselves or have you go back through and do it.
And one last note: a lot of writers overuse italics. Make sure it's really needed before you use it.