Since Internet Explorer is not supported anymore by most websites Safari has become the new worst browser in regards to having really bad CSS and Web API Support.
One important thing not mentioned here: Apple should make sure to keep up Safari Development. It's by far the worst browser available and the web platform is only growing.
The company I currently work for still actively uses classic ASP in production and they still actively develop that product. Currently trying to get away asap, because I don't wanna touch spaghetti vbscript from '99 with a ten foot pole.