I'm thinking that there will be diferent ways to use it other than swinging the thing around. With the add-ons, Im sure that there will be some sort of "standard" controller implimentation, like with the joystick (which has 2 z buttons on it, BTW) you could use the joystick to move your character around and use the main part to select things to attack. And yes, there may be some attachments that are game specific (i.e. bongos) however, they will probably be rather affordable.
As far as there only being "gimicky" games, I don not think that will be the case at all. THQ, Activision, Ubisoft, and heres the big one, EA all said that they all will support the Revolution completly, and already have games in the works for the system. I'm sure that some of the release games will be sort of like the DS release games were, but also like the DS, the games will grow up as the hardware grows more familiar. We have quite a few great games on the DS already (I personally own 16 individual titles and have liked each and every one of them).
I think that you need to see the broad picture here, and that is that Nintendo knows what they are doing, I WOULD say the same for Sony as well because they are an industry force too, (I'm not so sure if I would back M$ on something like this, due to the fact that they suck out loud). I think that we should just wait and see what happens, I'm sure there will be more info released this weekend at the Tokyo Game Show.
Do not fear change, embrace it.