The Bootstrapper is our name for steam.exe. We call it that because it is what does the client updates - usually just updating all of the Steam client binaries (DLLs) and other files, but also it can update itself. "Bootstrapping" is an old computer term for something that can update or re-write itself.

The geo-location algorithm is the process that Steam uses to find its location in the world, so that you get downloads from the servers nearest you. We made a change to this algorithm inside one of the other client binaries - steam.dll - several months ago. For the most part, that's the important one, and it has been very successful. However, the old algorithm was in steam.exe still, and there was a small chance that it could be the one used when your Steam client decided it needed to update that information.