So you enjoy having games d/c because the host leaves half way through a game, or getting put onto servers that are full of yanks who sound like they have just had their nuts put into a vice? With dedicated servers you can pick something that is not going to go down every half an hour or so and at least you can pick servers that are what YOU want to play, not what the stupid matchmaking process takes you.
It really annoys me having to pay £40 a year for something that picks for you to play not something that you want to play yourself.
Not to mention the god awful skill level of some of the players that are on CoD4 at least the servers on PC are of high skill level with good banter, I have yet to find one on the 360 or PS3 so far.
/rant over
Create your own player match and play how you want? it's not always about ranked games IMO, relax a little, play for fun, you are deciding to use matchmaking, it is not imposed on you.