There was a time when I had 3 bodies at one time but then I have quite a few lens too. I guess that was at the peak of my passion with cameras. And I did use them all. Non was a "showroom" piece and I was doing alot of freelance and FOC work as I was tryijg to learn more about my hobby.
These days I only have 2 bodies and out of the two, one has already been retired for a very long time after having been with me since the day I bought it brand new,the Nikon FG.
Ultimately you find a camera's basic function is really to take pictures be it film or digital. Sure auto exposure, more complex metering, faster focusing..etc has been steadily improving and in some cases by leaps and bound (abeit some of them are more marketing feature then practical) but you have to try to keep in mind too that...there were tons of beautifully taken pictures that has grace us ever since the early years of the camera. Again...all you needed was a basic camera with the ability to adjust shutter speed and aperture and a few lens to boot and there you go.
So essentially for me at least, I intend to stick to my D70 till it's end days. I did my homewrok back then and I actually was intending to get the D100 but in the end chose the D70 as it has certain technology which I find was a step better then the D100 and would be for sometime. I see very little reason to getting a new body unless there are features in the new one that will improve on the basics by leaps and bound in the practicality dept. Ya more advance metering is good but hey I have been shooting long enough to sometime be able to gauge the right exposure for what I want to shoot simple by looking at a scene. I could walk about in manual mode and not worry.
I would buy more lens if I can yes. I think differally at one time about lens but in the age of VR, I could see myself replacing ( if I can afford it and save enough) all my lens to VR lens. The added stability I think helps more then feature of focusing in my view. That I think is a worthwhile upgrade reason. And my promise to myself to try not to buy too many DX lens way back then has come full circle and I am happy my gamble that full frame bodies will come back within the life span of my D70 is true. I forsee in about 1-2 yrs that will trickle down to maybe the D400 or D90 or whatever model it will be...so we all can enjoy the full frame with our non-DX lens. It will then be buy buy buy day for me. I will only change when I see a need to and can justify it as the advancement in it has take a leap far enough to make it worth while in the practical sense, suits my ability and frequency of use.
But for others who are into collecting them when they could afford it, first line adopters or are willing to make the sacrifice to buy them as their passion for new technology is stronger then their need to use that money for something else..well more power to them. In any market...you need people like that to keep the advancement coming. You just have to remember that only you can make that choice to buy or not buy. If it is for the sake of your hobby in photography. Great, But if it is for something else. You really need therapy. haaaaa....