That's an highly superficial assessment. The real uproars had little to do with the UI, which had actually been previewed to favorable responses some time before the release.
No, what people were truly furious about were things under the hood. Or more precisely, things that weren't under this hood. Specifically, the lack of support for XML. What turned this from disappointing to infuriating was the simultaneous yanking of FCP 7 from the market, meaning that the entire FCP using community was frozen in place. It was actually illegal to add extra seats to a pipeline.
That's like walking into an air traffic control tower and smashing all the radios, then bombing the runway, just for added good measure. The difference is that Apple's customers weren't a hostile nation at war with the attackers. They were the attackers CUSTOMERS.
Indeed, the technology problems are almost a distraction. The real issue was the raw idiocy on display. I mean, this was stupidity on par with showing up drunk for a driving test. People were truly astonished that Apple could employ people this moronically dumb. And more to the point, that they'd give them access to a product with a LOT of exposure to the media industry.
If you think the situation was even remotely analogous to a Facebook redesign, you have no idea what actually happened.