Big news. A sensible acquisition on their part, considering how important they are for them and how closely they work together. A bit like Sony and Insomniac Games.
Consolidation isn't really a good thing, but it's the trendy thing to do right now. With MS and Sony buying up studios, it makes sense from Nintendo's perspdctive to secure some of their own necessary third party helpers for the future (by buying them).
Hopefully they will help them get to the... well next level. Sorry. NLG showed amazing promise by producing a close to 10M seller eith LM3. I'm surr Nintendo will want to develop them further and make them a steady producer of big games.