Not nearly enough people are comparing Halo 4 to CoD as these threads are popping up.
That being said I think that the majority of people that are comparing the two games are being severely misunderstood. Their comparisons to CoD aren't as far off mark as some people would like to think, and some successful game mechanics from that series are being brought over to Halo 4. There is absolutely nothing wrong with that.
But to say that Halo 4 is a new CoD game or that there aren't any comparisons to be made is simply inncorrect. Because it isn't and there are.