Yeah, 3.6.9 had several bugs which artificially inflated ping times so anything it gives is basically worthless. 3.6.10, however much I wanted to avoid it, also has a slight design issue held over from 3.6.9 which can make ping times higher than they should be because of some traffic issues. That will be fixed in the next FS2NetD rewrite though.
And as FUBAR-BDHR says, don't think of what the FS2NetD website says as really valid ping time wise. Those ping times are what that person/host gets to the FS2NetD server, not necessarily to anyone else. Ping times when actually in a game with that person could be far different.