In 2005, Microsoft made a big investment in quantum braids when it put mathematician Michael Freedman in charge of its efforts on quantum computing. ... But late last year, Microsoft hired several star experimentalists from academia. One of them was physicist Leo Kouwenhoven of the Delft University of Technology in the Netherlands, who in 2012 was the first to confirm experimentally that particles such as anyons remember how they are swapped. He is now setting up a new Microsoft lab at the Delft campus, which aims to demonstrate that anyons can encode qubits and do simple quantum computations. The approach is at least two decades behind other forms of quantum computing, but Freedman thinks that the robustness of topological qubits will ultimately win the day. “If you’re going to build a new technology, you have to get the foundation right,” he says.If it is "at least two decades behind", then there is probably a long list of technological problems to be solved.
Google and IBM are still promising something this year, I think. We will see, as I think Google and IBM are decades behind also.