> If you're starting a new web project today, you look at what technologies the browsers you're targeting already support with unmodified syntax. (I'd argue that that development model's a poor fit for the web, but that's a different question.)

If we really did that, we'd be back in the land of HTML4 and CSS2.1 and, ironically, Flash and Java applets.

I think the reality for most projects today is that we make a decision about how much portability pain we're willing to accept in return for using newer technologies to alleviate other pain such as making yet another set of rounded corner graphics, and we make a decision about how much degradation in the user experience is acceptable for older browsers that don't support whatever non-portable technologies we choose to adopt.

This is a far cry from what web standards should be, of course.

> That is an artifact of ClearType subpixel positioning.

That may be so, but the fact is that for several months lots of people using Firefox will have had difficulty reading lots of sites that worked perfectly well in older versions of Firefox and still work perfectly well today in other browsers (which makes me very suspicious of pinning the blame entirely on ClearType, BTW; no other software on these PCs has any trouble displaying those fonts).

If you're going to cause that kind of regression, then IMHO a policy of trying to force all of your users to update continually and ignoring the needs of those who can't or won't is inappropriate. Particularly in a security-sensitive application like a web browser, I think forcing users to choose between recent versions with vulnerabilities patched or old versions that actually did their job properly is irresponsible. After all, isn't this one of the reasons plug-ins are supposed to be Very Bad Things?

> I have a feeling you're choosing the font incorrectly.

Given that there is no standard specification of how to choose fonts like this, I think that's perhaps a rather bold claim to make (no pun intended). (Go ahead, check any W3C recommendations you like, you won't find it. In fact, the CSS2.1 Recommendation specifically acknowledges the variations in things like font weights between different families. It also provides no specific advice on naming conventions for font families at all, because what would you say that makes sense anyway?)

Again, it doesn't really matter though, because the point is that it worked on every other browser. Whether they are tolerant and Firefox is correct or they are correct and Firefox is broken doesn't change the end result.

> That's because most downloadable fonts aren't hinted for ClearType. DirectWrite with its subpixel positioning can cope much better with unhinted fonts.

Sure, but hundreds of millions of people are still browsing with ClearType, so I think trying to get professional sites to use web fonts that look rubbish in comparison to tried-and-tested screen-optimised fonts like Georgia and Verdana is one of those "Oooooh, shiny" policies that is more driven by hype than substance.

And for the record, a lot of the fonts available on the commercial font rental services render poorly even on high-resolution screens using the latest browser versions on Windows 7. I suspect the font services and foundries are banking on higher-res screens of the kind we're seeing on the latest smartphones making the need for traditional screen-font hinting obsolete. But this is drifting off-topic so I won't follow that avenue any further.