Yes, but no. GoDaddy didn’t swap Apache Web Server out for IIS resulting in the 5% drop observed by Netcraft and reported as a blow for the Apache Web Server elsewhere. As Netcraft say, the switch was from Apache Traffic Server (ATS), acting as a proxy, over to proxying with Microsoft IIS 7.5. When GoDaddy turned the Apache Traffic Server proxy on in May, after apparently testing it with content delivery networks in the previous months, 28.3 million sites appeared to be using ATS, numbers that were added to the Apache total, despite it not being Apache Web Server. This also made GoDaddy the operator of 99% of the ATS served sites out there. GoDaddy have yet to comment on why they switched to IIS 7.5.
The Apache Web Server numbers do appear to be trending down, but in 2009 it was at the same 47% share in raw hostname counting before rocketing back up. The raw hostname count and share is an interesting figure, but it’s counting a lot of dead ended sites managed by registration companies like GoDaddy and other services which use a proxy server to help front-end millions of sites behind them. This is why the graph flip-flops around like it does; one change in configuration at a major user of their proxy and boom, there’s a couple of million hosts just changed server. So deriving a proxy market share while counting these proxies is going to have a margin of error of “oodles”.
Back over in the working would though, Apache still holds 54% of active sites in the survey (number 2 is Microsoft with 15%) and 57% share in the top million (number 2 there is nginx at 15%). These numbers are better indicators, as they exclude the dead zones of the web, but they still count proxies. When reading these number, keep that in mind.