The Wired story was not accurate. It's true that some early (late 70s) UK electronic slot machines had predictable payout series, but this was quickly noticed a

The Wired story was not accurate. It's true that some early (late 70s) UK electronic slot machines had predictable payout series, but this was quickly noticed and fixed. It is trivially simple to build electronic slot machines that are not beatable by observing any reasonably short series of outcomes (for that matter, from observing over the lifetime of the machine). The successful electronic slot machine hacks in the last 35 years have all involved either measuring internal machine states or modifying the machines. In this case, the machines were modified to allow profitable play. This is done either to sell the machines to naive casinos (which is what the Russians did in this case) or to casino managers who use them to skim (the manager's confederates win money which need not be reported to casino owners or tax authorities). Another practice is to modify machines to extract the maximum amount from players, exploiting behavioral tendencies, rather than giving random payouts as required by regulation in most jurisdictions. Advantage gamblers sometimes discover these machines and use the knowledge to play profitably. But it's not enough to observe a few dozen outcomes, you need to know something about how the payoffs are structured. You won't find these machines in Nevada, because (a) the regulators are smart and powerful and (b) the place is too big a gold mine to risk over small increases in slots revenue. But there are lots of places with inattentive or weak regulators, in which slots is the whole ball game.