At 46, he's a particularly young appointment, which is apparently a purposeful decision on the part of Kimishima, who wanted a successor that could more easily connect with the company's customers.
“We will develop the company to its fullest,” Furukawa said at a news conference (per Bloomberg). “I will balance Nintendo’s traditions: originality and flexibility.”
Furukawa also speaks fluent English, so it's possible that we'll see him taking on the more public role that former president Satoru Iwata made so popular in his time at the head of the company.
Kimishima became president three years ago, following the death of Iwata, and his short reign was pretty eventful. Encompassing the end of Wii U, the rise of Switch, and the fruition of many of Nintendo's plans to license its IP to other companies (including the upcoming Nintendo theme parks), he was certainly busy. He was successful too, with Nintendo reporting that it's on track to hit its highest profit since 2010.
In another change, Satoru Shibata, president of Nintendo of Europe and host of many European Nintendo Direct broadcasts, will also become a board member. It's not clear who will succeed him at NoE.
Alongside the presidential announcement, Nintendo also revealed today that Super Mario Odyssey has hit 10 million sales as it updates sales figures for its biggest sellers. Joe Skrebels is IGN's UK News Editor, and he liked how Kimishima always looked like he was frowning, even when he smiled. Follow him on Twitter.