Now that the iPhone has been shipping for a couple of weeks you can expect a flood of accessories to appear. We've already discussed the case or no case debate, and I'm all about keeping my iPhone in a case.
My current favorite case is the DLO HipCase for iPhone ($35). This leather pouch case happens to work for me for a bunch of reasons. First it attaches firmly to my belt via a strong clip in the horizontal position. The orientation is important because the height of the iPhone can make it awkward to wear on your belt vertically.
Also it's made of high quality leather and has amazing fit and finish. The tan interior is a nice contrast from the black leather and white stitching. The HipCase has a nice snug fit that keeps iPhone from wobbling around but it's not so tight as to make it difficult to remove from the case. You can tote iPhone either screen in or screen out depending on your taste and preferred button/port orientation.
If you're looking for a high-quality leather case for iPhone look no further than the DLO HipCase.