I use only Nikon (F5, F100, D70, D2 plus lenses), but if you are looking at point and shoots, Sony/Kodak/Canon or Nikon are all excellent picks.
As for updating from a D50 to a D70, it will not give you any better photos. In fact a D50 is later technology. Updating to a D70
s won't produce any better photos, but it will give you more selections to pick from, and the D70 and D70s use the compact disc cards versus the SD cards used in the D50.
In fact, if you are looking for nature and landscape, the D50, uses the IIIa color space mode which is better, while the D70/D70s uses the Ia color space which is better for portraits.
To start getting more pixels and better resolution, color space, etc., you would have to jump to the new D200.
Just rememeber, pixels are not everything. Color space, dynamic range and sharpness is very important. The type of sensor (CCD versus CMOS) is very important too. Generally speaking, CMOS is not as good as CCD, unless you jump into the high-end (above 3K) cameras with CMOS sensors.
1COOLH3: We should get together sometime and shoot some photos. Like your site.
Here is a link to two AOL homepages, I have never gotten around to an actual dedicated website...yet. I primarily sell mine through studios.
Co/UT/AZ
TN/NC/VA/NY