There's no fundamental reason that things should play out either way (consolidation in a data center, or personal hardware). It will come down to economics, performance and convenience. Up until now performance (latency) has favored personal hardware, but it appears that may soon change, at which point the economies of scale of data centers, and the convenience of not needing to upgrade/store/maintain/move personal hardware, could very easily sway things in favor of consolidation.
