Something tells me that my post will contain nothing that wasn't already said a million times in this very thread, but...
PHEW, could've been much worse! I mean, Sega bought Relic, the studio I was really worried about. Sega already owns Creative Assembly, and the Total War games are pretty decent, right? Also, Sega now has a monopoly over the strategy genre, owning the only two studios in the industry capable of producing really good and innovative strategy games. Maybe we'll even see another Honeworld!
Ubisoft buying the rights to South Park is kinda sad, becasue they'll shoehorn that appaling of theirs DRM into the game as usual, but aside from that I don't really think these are reasons to worry about the game itself. Okay, that probably means that I personally won't buy it, but the game itself will most likely be decent.