Nintendo's involvement with Youtube and the people who do let's plays of their games is well-known. The company's stance to those videos who earn a living by reviewing games in video-form was simply “don't do it, or if you do be prepared to give us all the revenue from it” and led to many, many content creators simply deciding not to do Nintendo content as it was simply more trouble than it was worth.
Now it seems that Nintendo has relaxed its policy. Reviewers and Youtubers who make their living from gaming video content can make and monetise videos of Nintendo's games now... as long as they're prepared to sign up to what the company calls an 'affiliate program'. These programs are arrangements made between ad companies, Nintendo and Google and mean that the revenue gets shared between the video maker, Google and Nintendo.
While it's a step up from the previous policy, it's still probably not what Youtube content creators would hope for. As of yet, the standards of the program is unknown which could mean smaller channels might get rejected. Either way, this new policy might not convince those who swore off Nintendo content to start making it again.