The EOS 5D Mark II is released, and immediately, all the popular web forums are flooded with messages of how lame the new camera is and what Canon should have done.
To me though, the single most important thing in a digital camera, SLR or not, is the sensor. In the olden days of film cameras, you had to buy different film to get different ISO levels or to achieve different looks (such as black and white or fluorescent light films), but with a digital camera, you can just turn the ISO dial and adjust the white balance. So to get a different "look" or to get higher ISO levels means buying a whole new camera body instead of just changing the film.
Both the 5D Mark II and the previously announced 50D have improved sensors with higher sensitivity and more megapixels (however, more megapixels is not always better). The other improvements in the body such as better looking LCD, somewhat improved interface, automatic sensor cleaning, or even HD video, are just bonuses that are nice to have but have no effect on the image quality.
I'm very happy with my 30D right now, but the 50D had me drooling all over it just because of the new sensor. I'm also drooling all over the new EF 24/1.4L II lens.