Tristan Nitot asked:

1) Have a strong case for why it's useful.  (Yes, I am smart enough to understand these items, and why they're important - but everything is a priority.  Why are these MORE important.)
2) For video, the codec problem is a bit of an issue.  I can totally see implementing <video> in IE; offhand, I don't see Microsoft taking on the IP exposure (==$$$$) of implementing and shipping Ogg Theora or another new, theoretically "IP-clean" codec.  At the same time, if we were to share support for at least one codec and package with, say, MacOS, I think the essential problem for web developers has been solved.
3) The ideal way - and I said essentially this during the panel at Web Directions North last week - is to ship web applications and properties that use those features today.  If there are leading web apps that need <canvas>, SVG or some other big feature, it's more clearly necessary, and no one can ask the question "well couldn't they just use Flash/Silverlight/VML/whatever to do that?"  Bespin being built on canvas is an example (though in my mind a bit of an odd choice).

I'd (obviously) prefer not to be quoted publicly out of context on things like this, BTW.  None of what I say should be translated into "IE is going to ship <video>!" or "Chris said just use Silverlight!"  If you think I said that, please run it past me first.

-C