Did anyone ever think that Nintendo invented things ? Because that's just plain wrong. The NES was created using the tech that was cheapest to use at the time, and I think that the D-pad was used because it was cheaper than a full joystick - especially if they were to perform digital functions either way. The SNES used off the shelf parts as well, as did many Nintendo products (most recently - the DS which uses 2 ARM chips).
Regarding innovation - that's another story. Accelerometers have been around for a VERY long time, and people tried to implement them in gaming controllers more than once (MS being one of the 1st to try), but Nintendo simply did it in a way that works pretty well, and pretty much forced devs to work with it - something never done before.
Nintendo is an innovator in implementation - they take existing techs and find how to best utilize them.
BTW, most of Nintendo's innovations have been in the control department, and have never used "new" techs - the D-pad, the analog stick, the shoulder buttons, the wii remote- all used commonly available components, but used them in ways that made them feel good.
