One is somewhere hot (North Carolina, Apple) [1]
The other is somewhere cold (Sweden, Facebook) [2]
Hot, (assuming more solar energy available) benefits are increased power from a solar plant but the farm requires more cooling. Cold, requires less cooling therefore less energy.
It's interesting [to me at least] because it raises the question of efficiency. i.e. do you build something that requires loads of power - but who cares 'cos we got tonnes of renewable energy... or do you try an require a lot less energy even though hydroelectric is not damaging to the environment the more you produce.
[1] http://arstechnica.com/apple/news/2011/10/apple-building-171-acre-solar-panel-farm-to-power-nc-data-center.ars
[2] http://www.techiespider.com/2011/10/27/facebook-build-server-farm-northern-sweden-arctic-circle/