And fear not of the new sony/microsoft consoles. With the Move and Kinect only a year old, they'll keep on milkin that cow until it gets old. Give it about 2 more years.
As far as platformers vs open world stuff goes: Everyone has different taste. Mario galaxy never appealed to me much but NSMBW did as was the case with many others.
As for 3rd party titles just look at the Nintendo E32K11 press conference. They've got (Good) 3rd party titles coming out the butt now.