Book Titles

What kind of copyright you talking here? Like a registered copyright? I figure if you do that, you'll probably have to register another copyright.

If you just mean the copyright that exists from the moment you write something down, then it really doesn't matter.

I couldn't say about whether you'd have to re-copyright (my gut says yes, but it has been WAY wrong before). From a marketing standpoint, unless you're a big name, I'd leave the title alone. As writers, we tend to notice the byline. Readers pay much less attention to that.

You might run the risk of confusing readers, although more people bought 'Blade Runner' than 'Do Androids Dream of Electric Sheep'. Unless the title isn't working at all, I would leave it alone.

Speaking as a reader, it does more than confuse. It's annoying as all-get-out. It's like reading a book by a British publisher, then seeing another title by the same author, thinking "Yippee, a new book!" then finding out it's the same book, published in the US under a different title. Seriously annoying. Mystery series do this a lot. The old D&D Manuals used to do something similar: Keep the title, change the cover art.
My advice, unless you've sold less than two copies, live with the title you chose first, use the new one for something else.

Heck it's your book, change it if you will sleep better. )

It is absolutely okay to change titles (and you can't copyright a title, anyway, but you can copyright the contents of your book). I've seen this happen a lot especially on Agatha Christie mysteries, for some reason. As a reader, I welcome a notice when this is done -- such as, Formerly published as, The Labors of Hercules.