I found this to be an interesting primer on quantum computing. One take away for me is that quantum processors will be useful for specific purposes, not necessarily as general purpose devices. This implies to me that we might someday have computers with separate quantum processors with specific jobs delegated to it by the classic processors.
Another take away is that a lot of energy has to go into insuring that the qubits, the basic processing units of quantum computing, are isolated from the environment to prevent premature decoherence. It’s why so many of the quantum computing prototypes operate near absolute zero temperature.
One thing I didn’t get (I might have missed it) is how soon practical systems are expected. It seems like quantum computing requires an expensive rig right now. Of course, the first classic computers were also outrageously expensive, so there’s good reason to think time will eventually smooth that out.