I’ve been thinking a lot about hardware acceleration in CSS animations because of the current theme of Let’s Make a Framework. There is actually a lot of scope in CSS3 and HTML5 to create animations, and in some ways you can improve performance over traditional design techniques.
In Making an iPad HTML5 App & making it really fast, Thomas Fuchs discusses techniques he’s discovered for creating turbo-charged apps on Mobile Safari. Most of these techniques are relevant to other modern browsers.
One point that I like is “Images slow things down immensely — get rid of them”. Thomas recommends using techniques like gradients for buttons and backgrounds rather than using images. I’ve been building buttons in 100% CSS instead of using images lately because I’m a programmer and writing CSS is easier than messing around with Photoshop. I never really thought about performance advantages though, I just liked the way the results looked and how they scale nicely.