#4 - Aug. 28, 2007, 3:47 a.m.
As Kozzae said it's simply pre-loading partial patch 2.2 data. Before a large patch is released we may release small parts of it that we can generally guarantee won't change before release. This helps with data distribution by spreading it out over a longer period of time, and lessens the need for most people to grab very large files on release day.
- edit - Ok I'm going to look into it. It may be that the PTR patch is being forced for those that have the client installed, even when attempting to access the normal game/realms.