This is a really goofy NYT piece on Pavarotti's high C, claiming that his ability to hit the note with excellent quality "played a role in projecting Mr. Pavarotti’s fame around the world."
Good grief. Pavarotti's high C's were great, but I doubt you could find an expert who seriously thought it would have made any difference in the effect of Pavarotti's voice on an audience had his range topped out at B below high C. (That's the highest note in his "signature" aria, "Nessun Dorma," after all.) The fact is that his entire upper register was spectacular and rarely matched in its quality (in large part a function of his distinctive formants) and facility. That, and not a half-step difference in vocal range, is what "projected" Pavarotti's fame around the world.
Still, the article does recount a cute joke about Placido Domingo's reportedly weak high C:
[Domingo,] who extended his voice up from the baritone range and who is widely admired for his musicianship and artistry, is also not known for pinging high C’s. An unkind joke among singers has him dubbed “Mingo.” “Where’s the ‘Do?’ ” someone is asked. “He doesn’t have one,” goes the answer, “do” being the singing syllable for C.