Especially with a steam shower, if you've got the option, you'd be best to put the windows out in the bathroom, and NOT in the shower. Even glass block. Any intrusion into the wall is a potential way for moisture to cause a problem. There ARE ways to combat the problem, but it's just more added cost that's unnecessary.

Well, I wish I didn't have to have a window in the shower...but I do. Are glass blocks any better than a regular window? I don't love the look, but may consider it if it is better...I obviously need to drill the contractor when he comes out...any warning signs from him I should watch out for?

No, they're not. You're actually better off with thermopane windows.

I am in the same situation. The only outside wall is above the tub at the end of our 5x10 room. The bottom of our present window is about mid-torso. I am planning to fill in the bottom half of the window so it is more private. Since this would now be a small, high window I thought glass block would be a good idea. My other thought was to use an awning window. At least then I would still be able to let air in or out.
Bill, do you recommend a fixed thermopane or a window that can be opened?

If it's a normal shower, either one will work, although the fixed is better (easier to "button up" to make sure moisture doesn't escape). However, if the window's up high, and it's a normal shower, it really becomes a non-issue.