Back in 2003, Honda released Cog. It was an amazing advert. I even ordered the free DVD - there was no YouTube back then. If you haven't seen it, it's worth watching - it has no CGI and no smoke and mirrors. It, apparently, took 606 takes.
Flow, on the other hand, has to work well, if not flawlessly, first time, on all sorts of web sites we have never seen before. Increasingly often, I'm pleasantly surprised when I try a new website and it works pretty well, despite us not having spent any time investigating or fixing bugs specifically for it. Here are a few I've tried since we made the Acid tests pass:
YouTube renders mostly correctly, and now functions well, despite us spending next to no effort on it. It's fair to say we have automatically tested loading the home page daily for several years to ensure it doesn't crash but, until now, not interacted with it in any substantial way.
Microsoft Outlook is, perhaps, a better example. As far as I'm aware, no one in the team tried loading Outlook until yesterday, but it seems to work very well, though it has a few alignment issues. I sent my first email, using Flow, to myself without problems. I'm particularly impressed with this as it's probably just as complex as Gmail, yet is mostly functional with all the animated menu effects.
Another site I tried is Tom's Guide. I found it when experimenting with using Flow as my primary browser and was looking for a new vacuum cleaner. It rendered well, but a few paragraphs were incorrectly styled. I noticed, on the console, it needed performance.mark() which happens to be the feature I'm currently working on. Trying it in my development tree fixed that console error and all the styling problems had gone away - it turns out it programatically loads a stylesheet, but the uncaught exception was stopping this.
eBay is also a good example of a page that I've never tried using properly in Flow before. It has very few minor rendering issues, but I can navigate around, search for products, and I've just bought a pair of brake blocks for my bike, all without any problems.
Most other sites still have a few rendering issues - icons missing or incorrectly vertically aligned, or a bit too much whitespace here and there. They obviously do matter, but we can address these later - if, indeed, they haven't gone away in the process of debugging a different website.
I'm not claiming Flow is able to work well with all websites yet, certainly each of the above has some rendering issues. It is still some way off being able to be used as a general purpose web browser, but I am regularly surprised, sometimes amazed, when I find a complex web page that looks and works so well, the first time I try it.