With a browser supporting JPeG images see the following screenshots of a table with most XHTML style tags (excl. <q>, <abbr>, and the doomed <acronym>) rendered by Netscape 2.02 (= 3.x), Netscape 4.61, Lynx 2.8.5, and WebEplorer 1.1h. Only Lynx supports <del>, but all support <s>.
By declaring <s> as deprecated the W3C introduced an incompatibilty with legacy browsers for no obvious reason. This is much worse than dropping the name=-attribute of <a>-tags in XHTML 1.1, because it's not only annoying but potentially hiding the most important semantical aspect of a document. Many diff-marked W3C-documents are perfectly unusable with legacy-browsers, because deleted parts marked with <del> instead of <s> are shown as ordinary text. There should be a DTD for compatible documents, and in this DTD <del> would be verboten.