The HTML5 Family
My favorite open source HTML5 video player
An interesting presentation on HTML Video
In case you haven’t seen it this is the coolest Flash player alternative to the HTML5 stuff.
These guys also make an add-on to jQuery.
Google open web standards support.
iPhone specific interface stuff:
a must see CSS3 Canvas Animation.
Can’t forget Smashing Magazine
And to end it all there’s W3Schools which is one of the best learning resources I think for getting into this stuff.