SVG
--
All modern browsers support SVG. For legacy browsers, you can use svgweb as a flash-based polyfill, or develop with Raphaél which has a VML renderer for oldIE.
-Canvas
--
FlashCanvas or excanvas are your polyfills of choice if you absolutely need it.
-Video/Audio
--
Use mediaelement.js as polyfill for API (flash fallback w/ consistent visual design too).. Video for everyone base setup if No polyfill desired.
-CSS3 Selectors
-- -
data-*
attributes
- -
GROOVY everywhere obv. old browsers ignore unknown attributes, you can always use getAttribute
or you can use the dataset polyfill for IE8+.
CSS3 Transitions
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shim layer recomendded to get hwaccel with js fallback (isotope, yui transition, scripty2) ... or let it degrade
-CSS3 Animations
-- -
border-image
-- -
box-shadow
-- -
box-reflection
--
Webkit only. Dont use.
-font face
--
don't use cufon. use google webfonts or fontsquirrel generator
-<input type=range>
- -
We recommend you use blah blah, and use frank yan's polyfill or freqdec's.
-<input type=color>
- -
experimental use only
-