This is a huge win for anyone hosting data that falls under Japan's very strict privacy and data export restrictions, and shows Linode is definitely competing for space in the professional hosting market.
Most providers offer a Japan hosting solution as the second facility in the APAC region after opening in Singapore or Hong Kong. Sing/HK is used for the bulk of the hosting business so typically the first offered but a Japan presence is next up, regardless of size, to offer a complete global solution for customers who handle data that must be within the Japanese borders in-place.