Every day you can go on any forum or major online publication and read insults and complaints regarding Nintendo's tendency to keep releasing games from existing franchises. Although Nintendo has created several new IPs in the recent generations, still the complaints regarding the oversaturation of Mario titles and other well known mascots continue.
But I would argue that each new IP actually limits the number of sequels and reiterations of our most beloved franchises, much to the chagrin of Nintendo fans across the globe. I for one expect a new Mario (2d, 3D, Paper), a new Zelda, a new Metroid, a new Smash Bros., a new Mario Kart, etc, etc, every generation. These mainstays are the main reason I purchase a new Nintendo console. The one generation where I didn't get a Metroid, the 64 generation, I didn't purchase the console.
I'm not against new IPs. I love Pikmin, Chibi Robo, and the slew of WiiWare titles that have come out in recent years. But at some point Nintendo's software teams will be so large and spread too thin to both excite new gamers as well as satisfy the ravenous nature of the old school fans.
What means more to you: seeing your favorite franchises updated and reimagined with each generation, or experiencing brand new games set in brand new worlds, particularly concerning Nintendo franchises?