Raw

It seems Apple are asserting IP claims on the <canvas> element, which apparently did come from Apple but has since been taken up by the WHATWG with implementation support in Opera and Moz. As Arve says : "This has the potential to make people upset".



W3C-bashing has become a popular sport (with some justification IMHO in certain areas), but one thing they do get right is having a royalty-free patent policy - in short "W3C will not approve a Recommendation if it is aware that Essential Claims exist which are not available on Royalty-Free terms.". Using Dan Connolly's words from a completely unrelated context - integrity is job one.

fwiw, XHTML easily covers the 80/20 mark for me, even if having to Tidy is iffy. Having said that, HTML5 seems a great idea for working with HTML as deployed (so Tidying won't be needed), but I have doubts about it being the best route to new features. Modular namespaces seems much cleaner and a lot less hassle than piling everything into one bag - but then I'm not a browser vendor, nor do I work on a search engine that seems to consider most markup as decoration and doesn't understand standard media types.

The <canvas> element at risk? Just use <svg>.