Simple function to determine whether a given CSS property is supported or not. Useful for conditional execution of JS animations, rounded corners, etc.

detectCSS.js

// Is the passed CSS property supported?
// eg. detectCSS('transition')
function detectCSS(prop){
	var 
		prop = prop.replace(/-(\w)/g,function(s,g){return g.toUpperCase()}), 
		pre  = ',Icab,Khtml,Moz,Ms,O,Webkit'.split(',');

	for (var i = 0; i < pre.length; ++i){
		if(i==1)
			prop = prop.slice(0,1).toUpperCase() + prop.slice(1);

		if(pre[i] + prop in document.documentElement.style)
			return true;
	}

	return false; 
};

Dropped hyphenated notation in favour of camelcase notation for vendor-prefixed property detection, so it works in FF again.