Using a complex set of criteria such as seafloor geology, water depth, sediment thickness and a number of other factors, states with a coastline have the opportunity to expand their offshore territories.
The significance of this initiative is that this is probably the first time in human history, that all nations bordering on a coastline, can potentially adjust their territorial boundaries (including with neighboring states) in a peaceful manner. Considering some of the oil reserves and other ocean resources involved, the outcome will change the world's political boundaries forever.
Of personal interest and direct past involvement is the ongoing debate on how to divide the polar region. Depending on the methodology used, the results vary drastically.