Ah since we are going there I would add Bocelli. He always closes with Con Te Partiro. Brings a lump to my throat every time.
I like Bocelli, but for the connoisseur of opera, there is truly no comparison to Pavarotti. I have also recently seen a promising youngish male opera singer, Salvatore Licitra, who has performed at the Met and La Scala and is being called "the new Pavarotti." To me, Licitra's voice exceeds Bocelli by far; in fact, if you had never heard Pavarotti, you would say Licitra's is the best voice ever. But Pavarotti was singular, unique, head and shoulders above and beyond.
Just as there was a long gap between Caruso and Pavarotti, I doubt that Pavarotti will be equalled any time soon. He had an astonishing gift. Both times I saw him live, he was having an off day; even on his off days, his vocal quality was so extraordinarily beautiful and bel canto that any lapses in timing or nervousness (one time I saw him perform for Ronald and Nancy Reagan at Ford's Theatre and he was sweating and trembling) were nothing in comparison to that voice.