Dare Obasanjo writes:
Repeat after me, a web page is not an API or a platform.
Versioning APIs is hard enough, let alone trying to figure out how to version an HTML website so screen scrapers are not broken. Web 2.0 isn’t about screenscraping. Turning the Web into an online platform isn’t about legitimizing bad practices from the early days of the Web. Screen scraping needs to die a horrible death. Web APIs and Web feeds are the way of the future.
Consider it repeated. Just because people are using XHTML for their pages doesn’t mean that they’re following any specific data model. XHTML is meant to be both open and loose. As for screen scraping: ew, ew, ew.