Now COD 4 has got really bad lately for that.
One example the other day I was playing, we had just started, about 30 secs in game and there's an airstrike. Now they take 5 kills am I right? I thought that's strange so I looked on the leaderboard and sure enough the most kills anyone had was 3, so how can there be an airstrike unless there's something I don't know about and therefore I'm a noob lol.
This game can be the worst for being spawn-killed as there only a limited amount of spawn points on every map. When the enemy is spread out all over the map, chances are you'll end up spawning in front of one of them.
Maybe 2 things could solve this:
Choose your spawn point (maybe a little cursor on the map) prior to your next re-spawn
x seconds of invincability where you can't be shot or shoot anyone to get away from the spawn point
Could either be implemented? Maybe. Will they be? I doubt it...