I honestly think so, since whenever they actually do show any games they tend to at least be interesting ones. Indeed, for many other companies, it seems their E3 presentations are never anywhere near as good, especially the ones by Microsoft or Sony.
Is it because Nintendo have the more recognisable and interesting brands?
I would argue that Sony has had some pretty awesome conferences, though Microsoft barely seems to make an effort.
So far, Ubisoft really surprised me with 8 Wii U games including the helluvah pretty ZombiU game. Nintendo DOES tend to win (imo) most years though. Probably because I am not a fan of shooters.