Indeed. My 2009, 15" 2.53GHz C2D (with 8GB RAM) is still ridiculously fast for most things. I don't play any games, but for development, I don't feel a need to upgrade. I would love to upgrade of course, but that would be out of pure whim, not a need. I'll probably wait till next year's rMBP (hopefully it'll be cheaper and more powerful) and fully expect that machine to work for me till 2018 (that is, unless the battery dies on me).