https://www.youtube.com/watch?v=-ZNEzzDcllU
They claimed Quantum Supremacy last year with 50 qubits. Here, they're claiming it with 53 qubits.
What they've demonstrated is a general Quantum Computer able to outperform a classical computer. As they say, it would take thousands of years to confirm is a classical computer matched the quantum calculation. For all practical purposes, this Quantum Computer has outperformed classical computers. Assuming they start doubling the amount of qubits every nine months or so, then, Quantum Supremacy is here.
I should stress the General programmability of this Quantum Computer. There's a D-Wave quantum annealer, that is special purpose. The way they have to re-program it is like the Eniac, where they have to rewire it for each new problem. D-Wave has a quantum annealer that has thousands of qubits. But, it's not a general reprogrammable quantum computer.
Of further note, there's lots of different Quantum Computer strategies - superconductors(Google here), ions, photons, topological insulators. And, they're all making advances in scaling from basic demonstrations, to being able to make thousands of qubits.
