This is the pattern I have been seeing the last 2 years or so. Game releases (I'm going with game X to not turn this into a flame war or some idiotic argument). Then 99% of the time one of the 2 things happens...
1: It tanks, hard. The manufacturer panics and immediately slashes the price by 20/30 bucks and puts it on immediate sale to spark something. Even sweet games like Deux ex, Alice, and lots of other "mid tier" or "lower upper tier" titles have had this happen.
2: It's the sickest most badass thing on the planet. Which leads to it selling a bajillion copies and getting released as a "game of the year" edition a short wait later with more content, usually all the DLC included, and like half the price.
So assuming one has patience, what's the motivation to get anything at launch? The only exceptions I've found are the major sports franchises (if you're into those).