Disclaimer: Currently I am employed by Microsoft, but my views and thoughts are still my own. The reason I joined Microsoft was, the work Microsoft have been doing for last couple of years in Open Source Space. Today I am a advocate for Open Source representing Microsoft.
According to Microsoft:
More than half of the world’s population lives within about 120 miles of the coast. By putting datacenters in bodies of water near coastal cities, data would have a short distance to travel to reach coastal communities.
This is a important step for Microsoft to achieve the mission of: To empower every person and every organization on the planet to achieve more.