I mean the reviews mean nothing in the sense of Halo 3 and GTA 4 and MGS4
While i would typically agree with you that reviews mean very little these days i still have high hopes. This is because Killzone 2 has had more public exposure than all three of those games. MGS4 and GTA4 were never seen by any consumers until release day, Halo 3 was restricted to a closed beta, Killzone 2 has had public playtests of the single player and a long running closed multiplayer beta. Everyone i have spoken to who has played either of those has had nothing but praise for it.
The single player is most likely going to be fantastic, i do have my worries about the server issues you speak of too however.