Tony Soprano is dead. (So are Carmela and AJ.)
I've been denying his death all week. I've been telling myself that David Chase intended the ending to be ambiguous. But it's not.
As Bobby said in the final half-season's opener (a comment repeated in the penultimate episode), "You probably don't even hear it when it happens."
No, you don't hear anything. The episode ends in silence, a series first.
And yes, the onion rings were Eucharist wafers -- specifically, viaticum, the Communion given to a person dying or in danger of death. (By the way, "viaticum" is a Latin term meaning "provisions for a journey." Oh yeah.)
Too obvious? Compare Chase's visual onion-ring-on-the-tongue metaphor to this excerpt from Stephen Crane's The Red Badge of Courage:
The youth turned, with sudden, livid rage, toward the battlefield. He shook his fist. He seemed about to deliver a philippic.
The red sun was pasted in the sky like a wafer.
Speaking of hell, that's where Tony is going, of course. Because even though he did take the last sacrament, he never repented or even confessed to his family the depth of his sins.
(And the final season foreshadowed Tony's trip to hell. In the 81st episode, "Chasing It," Carlo tells Tony about a Twilight Zone episode in which a dead gangster meets a guardian angel type figure, and finds himself unable to lose when gambling and able to seduce any woman or have anything else that he wants. Of course, he gets so bored that he begs the angel to send him to the "other place." The kicker: The angel tells him, "This is the other place!" Later, in the peyote episode, Tony bangs Christopher's lady friend and finds himself winning at roulette again and again -- essentially, Tony is doomed to succeed.)
So Tony, Carmela, and AJ die -- probably all shot by the Members Only -- i.e., Mafia -- guy coming out of the bathroom.
But Meadow, who did not take part in the Last Rites, lives. And we know from Carmela's comment about her changing birth control, she's carrying the Second Coming -- Tony's unborn grandchild.
And what rough beast, its hour come round at last,
Slouches towards Bethlehem to be born?