I didn't realize OEMs would be shipping even the cheapest desktops and laptops with an i7 chip... I may have to reconsider building my own rigs

It's also obvious that games will become more demanding

It's a high-end feature now, sure, but it's one that I can see gradually filtering down the whole range. So a few years down the track from now, it may indeed become common

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The vast majority of games do and will limit themselves to whatever consoles are current, and can often have various things turned off so they'll run on even less powerful systems. Given that the Xbox 360 has been around for over six years now, consoles tend to use hardware that's slightly old from the start, and half a decade is reasonable to expect from the next generation, low-end desktops and laptops will have plenty of time to catch up.