There are some good sample pictures from both the NX73V and the NX80V in the reviews at www.pdabuyersguide.com. NX73V NX80V
The quality really depends on your eye, I suppose. For me, the camera on the NX80V is awesome. My stand alone digital camera was an older Panasonic 1.3mp camera that used SD cards. I liked it because, at the time, 1.3mp was OK, and the SD cards could be popped out and put right into my iPAQ. However, once the gadget buzz wore off, I never (*never*) used it. It sat on a shelf in my room collecting dust. There were plenty of times I had wished I had it -- but how was I supposed to know that I would need it that day? It's not something I'm always going to carry around, considering my pockets are already filled with cell phones, PDA's, keys, wallet, change, etc. But I am always playing around with my NX80V's camera, because it's always with me. The pictures are great quality, and the camera software from Sony has some excellent features (white balance, etc) for tweaking my results.
However, other people will see the high resolution digital camera on the NX80V as a horrible camera, and a waste of space on the PDA. Because it has no flash, and or because it has no optical zoom. There is a similar argument going on in the NX90 forum over it's 2mp digital camera. If you end up using the NX73/NX80 as your main digital camera, great. Good for you. If you buy an NX73 or an NX80 -- even an NZ90 -- and EXPECT it to replace your main digital camera with flash, optical zoom, etc, then you are only setting yourself up for disappointment.
Is the extra 1mp (the NX80 is actually the only CCD of the two -- the NX73's camera is a CMOS) on the NX80 worth $100 over the NX73? I don't know. It was never really a main consideration for me. I was never really interested in Just the digital camera on either unit (which is possibly why I was so impressed with it). I purchased the NX80V over the NX73 because of the extra 5mb of user available RAM, and it's much larger heap memory.
You seem to be putting a bit more attention to the digital camera aspect of these devices, though, so I can't really recommend paying the extra for the NX80 over the NX73, as neither may be a true substitute for your digital camera if you are serious about photography. You will notice in both sets of pictures that there is a lot of noise (static) in the pictures. I'm not really sure what causes this. Also, because there is no optical zoom of any kind, both devices have what I would call an optimal focus range. Basically, a couple of feet from the camera for quick and dirty shots of something. The camera will not re-focus for a macro mode if you are really close to something, nor will it allow you to adjust your focus manually.
However, if you are already getting an NX Clie, and are now just trying to determine if the camera quality is any good, then I would have to say that it also depends. Are you planning on viewing these final pictures on your Clie, or moving them to your PC? I have a CMOS (640x480) camera on my Nokia 3650 smartphone. I took a picture of my Clie with it's camera, and then a full size (1280x960) picture of my 3650 with the Clie camera. I then beamed the Nokia's picture to my NX80 via IR. On the NX80's screen, both images were reduced to about the same size. The subject for each photo was pretty basic -- a phone or a PDA in an indoor environment under florescent lighting. Maybe if these were outdoor pictures, or something with more color, more detail, I would be able to tell a difference between the images at similar sizes. However, they looked pretty similar on the NX80. I then beamed the large Clie picture to my phone, and then e-mailed both pictures to myself here at work. When displaying them on the computer, however, the Clie's picture looks much better than that of the CMOS camera on the 3650. Of course, this is not really a true test of the NX73 vs the NX80 as I am assuming that the CMOS camera on the 3650 is the same quality of that on the NX73.
I hope some of this helps.