I would seriously suggest Kanan Makiya, an Iraqi intellectual on the faculty at Brandeis.

Here's a story in the NYT today about him.

Okay, I just told you what Apple wants you to look out for with window positions, but in the real world, not everyone uses the hiding feature of the Dock, and it is unrealistic to be able to predict where each user will place their Dock at any given day or how large they will have it. However, you can build a feature into your application that allows spacing for the Finder. You can give users the option of where to position their windows and what area of the screen not to cross. I know that BBEdit provides me with this feature, and I wish more developers gave me more control over my windows.

The simple fact is that, when all other factors are equal, where will consumers spend their money? I believe that in the long run, the best looking, easiest-to-use applications will also be the most successful. I think that's why Apple encourages developers to write programs that are 100 percent Aqua-compliant.

Adhere to Window Models. Document windows, Utility windows, Click-through, Layering, Drawers, Controls. How do users open windows, how do you properly title windows?

Dock Animation. Sometimes animating icons in the dock can be useful in communicating the status of the system or application.

Adopt Sheets. I really like the use of Sheets in OS X. The use of Sheets lets me know which window my dialogue belongs to without hijacking my system.

User Assistance. This is helping the user with the proper "next step" when performing a task. Less guesswork for the user on what to do next makes for a better experience.

Dock Animation. Sometimes animating icons in the dock can be useful in communicating the status of the system or application.

But limit your animations to whatever is required to communicate the necessary information. Avoid annoying animations that discourage ease of use. Ask yourself, "What do I need to show the user, and what is the cleanest way possible to achieve that?" A good example is the Mail application for Mac OS X. Whenever a new message arrives, the Dock icon changes appearance to indicate a changed state.

This topic is one we will tackle later in this article, but it refers to making sure that your application and the dock aren't fighting it out for supremacy of the screen.

User Assistance. This is helping the user with the proper "next step" when performing a task. Less guesswork for the user on what to do next makes for a better experience.