Let the shopping spree begin? Where should they start?
As long as they're intelligent about the acquisitions, go for it. They shouldn't overpay just because they're open to acquiring a company.
My personal wish list: Wayforward Technologies, Mistwalker, Platinum Games, and Vanillaware. They're small and make games Nintendo themselves do not make (there's some overlap with Wayforward Technologies). Put them to work strictly making console games. These are low risk, medium reward acquisitions. If Nintendo could pick up MercurySteam, do that.
It will be difficult to acquire larger companies though if there's a decent one on the block, inquire. I think this only works if Nintendo allows them to do their own thing with minimum micro-managing. For example, if Nintendo acquires Company X who are working on a title then tells then to put Mario in it, that just isn't going to work.