I strongly agree with Upward.
Oh boy... All these Gizmos... The war will never end. I knew of these upcoming new babies since last month. But I couldn't bother to pay much attention to them.
Nikon's new D300 is the replacement of D200, seems to be such a good deal though... But ultimately, I wouldn't consider chasing any of these bodies. I'm happy with the 400D which I'm using for 11 months now. Though they may be bigger and better, ultimately, the output of an image is gonna be the same, more or less, image quality can be enhanced in photoshop, no matter which cam you're gonna use. It's like buying a car and changing it every 2 months when all you gonna do is just drive yourself around.
My 400D (XTi) has shot over 17,000 photos and still counting till today. It has undergone even openly harsh whether conditions. It has been exposed under pouring showers for 4 times (Not light rain) for nearly an hour over the past 11 months and it still works regardless of whether. It is surprisingly rugged despite many said it spoils easily.
Oh yes, with all that rugged use, it's important I send it to the Canon Agents every 3 months for cleaning.
In my opinion, these cameras are great, and it's a good sign Canon and Nikon improve over the years. But to chase every new camera that comes out every 1 year, with just a slight or a little more improvement of what you got... And with a same hefty price tag like how you bought your previous, that is something to consider before buying.
So in conclusion, I'm sticking with what I got, improving my photographic composition, subject and technique instead of improving the camera itself. That's ultimately what you do and use with the camera, isn't it?
Good stuff by the way.