The iPhone's camera is very simple and may only be 2MP, but it gets the job done well.
The G1 also has a very simple camera lacking configurable options, but it sports 3.2MP and autofocus. The catch is that the delays while taking a picture can be quite annoying. Waiting for the camera to focus is understandable, but a noticable delay of a few seconds between pressing the capture button and the camera taking the picture is unacceptable.
In terms of options, the Storm's camera wins hands down. It is 3.2MP, features an LED flash, autofocus, and a nice camera options menu to change everything from the resolution to white balance to applying an effect. I don't think that more options necessarily makes the best camera, but I would expect these features on all of these phones.
Post your comment and let everyone know which camera you think is best. I think that the iPhone is looking the best in this test, but that's just my opinion.