I read this article, specifically “One annoying interface issue that seems to happen so far with many iPhone applications is that they open in a very zoomed-out version, so the first thing you have to do is zoom the screen and drag. Even if a site is optimized for the iPhone’s 320×480 screen, you can easily scroll away from it into the blank area of a larger virtual page.”.

There is a way to fix that issue. Safari for iPhone introduced a new meta data called “viewport”.
HTML markup for viewport is as follows:

That will clear vastly empy space. If you specify viewport’s value, its default is 980 and because of 980 width, it will create empty space on right hand side if your site is designed for 320×480.

More detailed information can be found at this link.

From the documentation linked above, you will find really good resources on how to build a site for iPhone.

By the way iPhone rocks! ARGGGGG!!