I am experiencing the same issue.
They appear to information for the maps, instead of player classes by the names specified under them.
I can confirm this bug. Messed up numbers in the screen that shows while loading the map.
Looks like this was effecting all versions of TF2. The main TF2 team has checked in a fix for it. It should be in the next release of TF2.
Nothing extracted yet.
I wrote about this in another bug thread, but I think it may be different enough to warrant its own bug.
In my TF2 performance stats list, I have a lot of blank entries and a bogus play time. When I look at my stats page on the Steam Community site, I see all those blank entries in the Personal Class Stats are map names.
http://steamcommunity.com/profiles/76561197973545771/stats/TF2/compare
It seems like a really bizarre bug.