Honestly if they just made a killcam for the final kill on CoD I am pretty sure a majority of the player would NOT miss it. Personally I could care less about the killcam, I just skip over it. All I want is to get back into the action and go on a killstreak or kill the punk that killed me twice in a row . CoD is a fast paced shooter so having a killcam for every kill is kind of...not fast paced.
Being in Halo is an addition that is not necessary but it will be nice to see how it turns out. I doubt it will be in a gametype like Team Snipers but would it really change that much? I always find a sniper by its bullet trail regardless.
As for sniping in Halo and CoD it can be argued that they are similar because, to simplify it, you either sit down and camp or you run around no scoping.