Microsoft has announced that as from December 31, they will cease to support the Mac OS X version of Internet Explorer. The company is recommending that Mac OS X users browse the Net with Apple's Safari instead. The Mac version of IE is pretty out of date, and has not had an update in three years - hardly the kind of thing suitable for today's Internet, which is plagued with all sorts of security hole exploiting badness.
Web sites designed to work only with IE might have a problem; however more and more developers are looking to create Web sites that are standards-compliant and browser-independent, in order to avoid losing a large proportion of the market which incidentally does not use IE.