The Wand/Gem/Arc demos were about showing off potential uses for it. Maybe they didn't explain well enough because a lot of the talk after E3 seemed to miss that it used the PS Eye, something in already in stores that can do a lot of what Natal showed off (granted, not as good); even Eyepet has been out in Europe for a few months now, I think. Fault on Sony for putting the camera out there and ignoring it for all these years. The wand demos were just tech demos, and I'm guessing they expected the viewers to use their imagination to see all the uses a better, more accurate wii remote could have in games. Poor performance on their part. Then again, it is hard to really explain to people (or worse, the Wii audience) how all that techy shit will translate into more fun. Ignorance is a great thing if you enjoyed the waggling for years until Sports Resort and the two or so other motion plus games came out.
Natal presentation was pretty much filled with dazzle and promises and people ate it up. Instead of trying to just show why it's a better thing you already have, they showed off something totally new with full body control. Then there were demos of really broad splashing buckets of paint and shit like that. They also had Spielberg come out and, I don't remember what he said, but Speilberg was on stage! then they showed a video with Molyneux showing a totally real honest video of some daft blond thinking her TV was throwing goggles at her. And now news of the downgrade, only capturing at 30fps, etc. doesn't really change what they were trying to with Natal. For people who thought Natal might have some, you know, practical use in video games it is a slight disappointment, but the audience that bought into the Wii probably doesn't care.
Still interested in seeing how both turn out. I'm 99% certain the Sony wand thing will be a massive failure. Natal maybe has a chance to be popular, but I've given up any hope of proper motion controls.