as far as the Natal stuff, it looks like pure gimmick but it has since day 1. i'm sure it'll sell and make plenty of money, after all look at how well the Wii is doing. of course MS and Sony have put out similar devices; they've been building off of the innovations that Nintendo has created since day one. i'm certainly no nintendo fanboy, but they've been the only ones to consistently evolve the consoles with new ideas and technologies from the beginning. their hardware isn't as fast, and their systems aren't as strong, but from the nintendo, to the gameboy, to the SNES controllers (shoulder pads), N64 (analog stick), hell even the failed virtual boy have all been innovations, however gimmicky they seem. they still impact the market and lead to better product design by their competition.
the PSX and the xbox were both high powered copies of the N64, and their followup consoles have merely been upgrades to their systems. i think MS has done a good job with XBL! but hardware side there hasn't been anything that either company did first, iirc.
They don't have to innovate. I don't care if it's the same thing but faster. They just have to be better. Apple wasn't the first company to make a tablet. But they did it better. They weren't the first to make a cell phone, but they did it better. Blizzard wasn't the first to make an MMO but they took what was out there and polished it up. Nothing innovative there at all but still highly successful.
All microsoft has to do is make it better than nintendo and they win. And that's just fine with me.