Maybe people arent in a rush to get it or they arent interested in it.......games with high ratings such as ,uncharted 2 ,lbp , GOW, bioshock , The Orange Box etc. dont have the god given right to be bought by every single person owning a platform the game is on.
Some may not like platformers and some may not like shooters or maybe some people(myself included) arent interested in the game....just because a game has a high rating doesnt mean I have to buy it , infact I only own Bioshock in the list I provided above.
And the number of online players in a game is determined by the developer nothing more.....they could easily do 400-500 players in one map but would it be fun? Design is a very important part of gaming , I played a 64 player match in Resistance 2 and although it was handled somewhat well it still wasnt as fun as a 16 player game.
I could go on and on but there is no point as you and this thread are on borrowed time right now.