So how well does it work? Pretty well. Video was exceptionally clear and high quality, but then again it was on Apple’s website using highly optimized H.264 video. Playback was choppy at higher resolutions, but I blame that on my slower computer. All in all it performed just as well as Flash does. All the demos are pretty impressive, but it remains to be seen if web developers will put that much effort into it as Apple has. Also, keep in mind that not every browser full supports HTML5 and CSS3 + SVG, so these features may not all work exactly the same on Firefox, Chrome, or Internet Explorer (though the next version of all these browsers will probably fix that). In a bit of irony, I actually could not run one of the demos (the VR segment) because it requires support for CSS3 3D animation, which Safari 4 on Leopard does not support. I’ll have to revisit that one once I get my new computer for college.
So, what do you think? This good enough to replace Flash?