I was going to say something almost precisely like this. The main thing I was going to add is that it is both memory bandwidth and latency that have become important bottlenecks, and often the latter is more important. You know how people were saying "disk is the new tape"? Guess what the new disk is? RAM. Much as with disk latencies, RAM latencies haven't really improved that much over the last decade or so, though memory bandwidth and CPU power have. Guess what that means? ;-)

..but you can only know this if you understand what's going on underneath the hood. So if you don't, no need to worry; you won't even know when the moment of your utter irrelevance arrives.