The terrestrial fibre portion is expected to serve landlocked countries across South East Africa, bringing additional capacity to capital cities. This may lower the cost of IP Transit for ISPs and Mobile Operators in countries where retail Internet prices are still higher than average. The new route can also serve as redundancy for subsea cables along the East coast of the Continent - several cuts were felt on both sides of Africa recently.
It can only be a step on the road for Google, creating a worldwide, redundant system of seacables and terrestrial fibre to lower the cost to access digital content (and services) for its billion customers.