iPhone development and CSS3

I just bought an iPhone and so, naturally, being a web developer I've started looking at what can be done with iPhone apps. Having a look at one of Apple's demos (iPhoneButtons) reminded me that of course you only have to develop for Safari on the iPhone and therefore can use some of the nifty CSS3 features that are already available in Safari. Developing iPhone interfaces might be an interesting way to get to grips with a few CSS3 features where in a normal web project you wouldn't want to use them yet.