Hello,
I don't know alot about game servers stats as I've never tried programming these before. However, I do know that some games like Call of Duty have log files which various people have already written php or web enabled server parsers for them to view the stats, maps, scores and other details online.
I also know that there are various "Game Server Only" types of web hosts and some of the ones who advertise across the web are using some sort of status script that seems to show details for every server that they are running. I know this because I came across one and visited the site of the guy who wrote the script and noticed that it was open source. But now, I just can't seem to remember where I saw it or what the site was.
I will keep a look out and will reply again shortly. I just can't seem to remember at the moment.
Chris