Indeed. That's my biggest question at this point: what, if anything, is upgradable? I'm hoping at least RAM is still upgradable. I'm in the market for a new dev machine, and the Mac Pro just doesn't give enough bang for buck these days. However, I do find myself still upgrading RAM every year or so as Xcode's RAM usage gets higher all the time. It's much cheaper to buy just enough for now and upgrade later (when RAM prices come down) than buy more than enough now.