The number of cons, and the fact that there are no serious ones, is a testament to the thought and work that has gone into the D80's design. It's one of those cameras which just feels 'right and sorted' from the moment you pick it up. Things just get better the more you use the camera, you will begin to discover the usefulness of major features like the customizable automatic ISO and the subtle touches like being able to tap the DELETE button twice to delete an image (sounds insignificant, but in use things like this make the D80 far more usable than other cameras).
Spend some time with the camera manual and looking through the menus and you'll begin to realize the amount of customization available, with no less than 32 custom functions there's very little you can't configure to your way of working. Stack on top of this control over settings which are just 'defaulted' on other cameras (such as high sensitivity noise reduction) and it's pretty obvious that the D80 is in a class of its own in this respect.
In-use performance also feels as though it's a step above its price class, instant power on time and on to shot time, very fast auto focus, short shutter lag and 'just-about a blink' viewfinder blackout (160 ms), fast record review and playback as well as fast SD card write performance. There's also ergonomic performance, the camera is smaller than the D70/D70s but not at the expense of usability, the hand grip is a good size and shape (and considerably more comfortable than the EOS 400D) and all controls are within reach. Other small details such as button size and placement are simply just right.
Just as significant is the viewfinder. A digital SLR relies on its viewfinder for scene composition, focusing and depth of field, you do sometimes wonder how seriously this is taken. Nikon clearly did with the D80, instead of a light-sapping (but cheaper) Pentamirror solution they selected a quality Pentaprism setup which is, we are told, similar to that in the D200. That glass Pentaprism viewfinder with its 0.94x magnification equates to a big, bright view which has no distortion and really does bring you up close-and-personal with the entire scene. Optional grid lines can help greatly when taking landscape or architectural type photography.
So we've established that the D80 is a great 'photographers camera', but how good are the images? The answer is, really very good, Nikon appear to have shaken off the soft-image demons of the past and are also using a slightly stronger (more consumer friendly) default sharpening level than the D200. Resolution is as good as other ten megapixel digital SLRs, color response is vibrant, yet accurate, images are more contrasty than some other manufacturers but of course if you prefer a slightly flatter response you can always create your own custom parameter set.
Onto noise, Nikon's approach, as it always has been, is to use more chroma noise reduction and leave as much luminance (detail) information intact as possible. This does lead to more visible 'grain' in images at higher sensitivities than some other cameras but because this is monochromatic in appearance it is less digital-like, more reminiscent of film grain. Thankfully also if you prefer you can control the amount of noise reduction applied (although this appears to control luminance NR). To be fair the D80 does not perform as well as the EOS 400D (Digital Rebel XTi) at ISO 800 or 1600 but the differences are much less than they ever used to be, Nikon is closing the gap.
The last issue is price, or value for money. In my opinion, its customization, performance, build quality, comfort and design are worth the price difference between it and the competition. Having said that Nikon may struggle 'in stores' to fight Canon's (aggressively priced) EOS 400D ($200 is quite a big difference). If you're a more discerning photographer who can see the advantages offered by the 'all round' D80 you may well consider the extra money well spent.
