I do not see any significance in Shavit referring to Goldberg and Cohen but not to Ignatius. Shavit picked one widely read person, Goldberg, who is predicting war and one, Cohen, who thinks that Goldberg is mistaken. Seems he picked those two with opposing views just to frame the issue, his choice could have been from among many others, but not Ignatius. At least, that is, based on the one article you linked to.
 Ignatius merely talks about what is being said by various parties and offers no opinion of his own that I can see on whether either Israel or the U.S. will ultimately attack Iran. Shavit not referencing him is no more significant, or interesting, than not referencing you or me. Ignatius only stated conclusion is:

U.S. officials see two possible ways to dissuade the Israelis from such an attack: Tehran could finally open serious negotiations for a formula to verifiably guarantee that its nuclear program will remain a civilian one; or the United States could step up its covert actions to degrade the program so much that Israelis would decide that military action wasn’t necessary.

U.S. officials don’t think that Netanyahu has made a final decision to attack, and they note that top Israeli intelligence officials remain skeptical of the project. But senior Americans doubt that the Israelis are bluffing. They’re worrying about the guns of spring — and the unintended consequences.

Shavit's  whole piece seems not to be intended to offer more objective evidence of intent on any side but to say that his subjective opinion, based on what he claims to be close up and personal contact with key Israelis, is that there is good reason to believe those who claim an attack will happen.

On the other hand, what we journalists hear in closed rooms is staggering.  The officials talking to us seem to be genuine and earnest.  The sources are top-notch and what they say is consistent with what we know of the preparations being made by the IDF.   There are no blunt lies here.  There is no cheap spin.  So are we to self censor priceless information indicating war might break out soon?

His evaluation of their behind the scenes talk scares him that their publicly voiced maniacal threats are for real, that they are not a bluff.
  Panetta believes there is a strong likelihood of an attack. "Senior Americans" according to Ignatius, do not believe the Israeli threats of attack are a bluff. U.S. officials, he says, see two possible ways to dissuade the Israelis from such an attack, get Iran to submit to our demands or hit them hard enough with black ops that an attack is unnecessary. Goldberg thinks an attack will happen, Cohen doubts it, I am afraid, for all the reasons NCD lists and more, that an attack may happen,and you are tired of hearing about it. Life goes on. Until it doesn't. Your near term prospects, and mine, remain much higher than those of many who are on the dangerous part of the game-board.