What computers are smart at are brute-force calculations and memory retrieval. They’re not nearly as good at pattern recognition or the ability to parse meaning and ambiguity, nor are they good at learning. To continue with the subject of gaming, it’s worth noting that when it comes to games that are tougher to solve mathematically, computers aren’t as good as humans. And when it comes to strategy games, such as Starcraft 2 or the Civilization games, long-time gamers know that the computer AI doesn’t beat humans by being smarter–they beat humans by cheating: the program allows the AI, at higher levels, to do things faster than it allows the human players to. In essence, it handicaps the humans by forcing them to operate under less advantageous rules.
Now, I don’t doubt that computers are going to get better and smarter in the coming decades. But there are more than a few limitations on human-level AI, not the least of which are the actual physical limitations coming with the end of Moore’s Law and the simple fact that, in the realm of science, we’re only just beginning to understand what intelligence, consciousness, and sentience even are, and that’s going to be a fundamental limitation on artificial intelligence for a long time to come. Personally, I think that’s going to be the case for centuries.
I’m a Singularity agnostic, but I do think we – as a species – are really bad at predicting how fast technology will advance. In any case, centuries really isn’t that long in the big scheme of things.