The article mentions it also needs to span continents. I'm pretty sure that if you want to reliably transfer 100GB/s, you'd need to roll new cables between a couple of continents. North-America to Europe might have the capacity, but I'm sure (looked into it before[3]) that from South America to Europe can't do it directly even if you exclusively rented the cable that runs between the continents (which is the Atlantis-2). So you'd need to route through North America or maybe Africa, which adds latency. Probably still under 300ms single-trip, but it still seems unfeasibly large to me.
Even if the article is mistaken and means 100 gigabits instead of -bytes, I have a hard time believing it. It's possible, but hard to get that much data between continents while keeping the latency low enough, at least without rolling your own underseas cables which even Google doesn't do on their own[2].
[1] https://ams-ix.net/technical/statistics
[2] http://gizmodo.com/google-funds-an-undersea-cable-to-connect...
"The Tata Global Network(TGN) has Trans-Atlantic and Trans-Pacific data transfer capacity of one terabit per second." http://www.formula1.com/news/headlines/2012/2/13043.html (Two years old)