Before you jump all over me for repeating myself, a 100/100 score on the Acid3 test doesn’t mean you fully pass. Actually, you still need to complete the animation smoothly. While both Opera and Safari achieved the top score some time ago, only recently did Safari do it smoothly. Even better, it was the first browser to do so.
The reference hardware for the smoothness is actually something near and dear to us, the top-of-the-line Apple laptop at the time the test is run. That sounds to me like a business justification to purchase a decked out MacBook Pro to me. We all need a laptop capable of fully passing Acid3, right?
Congratulations to the WebKit team on the accomplishment. The work they’re doing helps motivates others to enhance their own browsers the same way. I’m a little perplexed as to why Mozilla seems to have so little interest in passing these standards tests as that seemed to be own of their original claims to fame.
I mean it's not really lack of interest, if you follow the Acid3 tracking bug on Mozilla, it looks like 3.1 will get up to at least 97/100, missing only svg font support. I think the current mindset is not to turn on parts of features that aren't ready for primetime just to get to a pass of the test.
Anyways I care way more about Tracemonkey and increasing javascript engine speeds.