Many of you have argued that XHTML served properly -- as application/xhtml+xml, that is -- isn't practical for dynamic Web sites. Simon Willison calls it "living on a knife edge:"
This is no small step to take - serving XHTML with the correct Content-Type causes Gecko based browsers to attempt to parse it using a real XML parser, and should it turn out to be well formed they will refuse to render the site and die with an error message. Since I use Phoenix myself and almost certainly visit this site more than anyone else I'm hoping I'll spot and fix any errors before anyone else runs in to them. Talk about living on a knife edge!
We've argued that there are real benefits to using XHTML properly. Indeed, we still believe this. But anyone visiting our site today saw why it's dangerous to turn your site over to an XML parser. For a few hours, one of the links on our site included a description within the title attribute that contained a quotation. Un-escaped quotation marks are illegal within attributes. As a result, our site failed, in the full sense of the word. Anyone visiting today -- for the few hours before we caught our error -- saw only an XML parsing error.
Looks like we fell off the edge of the knife.
We haven't stopped believing in XHTML. But we can't help wondering a few things. What if this were our business site? What if downtime meant loss of revenue? Our readers -- we think -- understand the benefits of this experiment. Would a client interpret today's failure as anything but incompetence? Of course not.