People are not CSS chalenged, browsers are. Especially the latest piece o work from M$. IE 6.
NN6x+, Mozilla and the latest in Opera, Safari and Konqueror good luck making something that will work in all of them and not be extremely simple.
Until browser support gets better, or there is a mass exodus from the use of IE, you really have a hard time making a site in CSS cross browser. HTML 401 transitional is VALID coding and can work in IE 3x to IE 6, NN4 to NN7...go for it for now.