This was worth downloading the latest WebKit nightly for. I first tried it in Safari 4.x, and was underwhelmed. I then tried the latest nightly, and was very impressed. This, coupled with hardware acceleration for the 3D transforms, could seriously eat away at the sort of territory owned by flash and silverlight.
The unfortunate part of this is exactly as you say--you first tried it in a bleeding-edge version of Safari, and it wasn't good until you updated to the latest nightly build.
That doesn't bode well for performance in other browsers like Firefox--let alone IE.
To clarify, it wasn't performance that left me wanting. It was still a usable Flickr browser. It just didn't live up to the headline until I tried the nightly. In other words: it degraded well, and this is actually a terrific validation of the extensibility built into the CSS spec. This isn't like the old days where you couldn't log into your online banking without IE. So I disagree: it bodes quite well, IMO.
