The Apple web site, which runs on Mac OS X, experienced some slowdowns but was largely available. Apple’s online store (also on Mac OS X) struggled, however, experiencing outages and lengthy response times. Faring even worse was the official site for MacWorld Expo, which runs on Windows Server 2003, and was offline for hours following the show’s keynote address by Apple CEO Steve Jobs.
The article at Netcraft includes graphs to illustrate the response times (or lack thereof). I don’t think anyone needs me to point out the irony in running a Mac site on Windows… or the ability of the “small” Mac audience to take down a Windows-based server.