This is a somewhat related question. I read that IIS was down to 24% marketshare and was surprised because I remember reading scare stories about Apache being overtaken not that long ago.<p>The latest Netcraft survey shows a huge hump where IIS has risen and fallen over the last three years, and the active sites (a newer metric that excludes placeholder sites) show a rapid rise for IIS before totally falling off a cliff after April 2009.<p><a href="http://news.netcraft.com/archives/2010/01/07/january_2010_web_server_survey.html" rel="nofollow">http://news.netcraft.com/archives/2010/01/07/january_2010_we...</a><p>Does anyone know what caused these trends? I paged through the monthly updates but Netcraft doesn't seem to comment at all on IIS losing half of its active sites, about 16 million, over just 6 months.