It's out there, but rare like you said. Just put your name on a list
at any site and you'll get one.

From what I've in some informal tests it's of reasonable image
quality, but it falls behind the 18-70 in a few areas. The new 18-135
does not have a ring motor so it lacks the high speed focusing of the
18-70 (although it has a silent direct drive motor), and it lacks the
autofocus with full-time manual override.

Aside from that it seems to be similar in performance (critical tests
yet to be done). It has low dispersion and aspherical elements, so it
should be a decent performer overall.

For general use it's probably above average.

I'm a bit more picky about focus speed, so I'd probably still prefer
the 18-70, but that's just me. Let's wait and see how it performs in
tests, and go from there.

I tend to agree with Bill for the same reasons, except for one thing.
The 18-200 is not quite as rare as reputed, except as a standalone
lens. There are plenty of D200 kits that include the 18-200 last I
heard. This would be the way I would go if I was looking for both body
and lens.

IMHO the 18-70 is a great all around lens, but you will have to change
lenses if you want to go longer.  I have the "kit" lens and an 80-200 f 2.8.
Aside from some other lenses I have, these cover just about everything with
excellent results.

The three lenses you mention have been tested by Imaging Resource using DxO
Analyzer. The results can be seen at IR's companion site SLRgear.

Depending on your needs, all of the above lenses are somewhat slow.  The
18-70mm is a super lens, if it's fast enough for your requirements.  If
you're planning on doing a lot of low/natural light, or action photography,
you might want to spend a little more now (than later), and go for something
like the 17-55mm f/2.8.

Bill Crocker

If you want to do work in the near Tele range (e.g. Sports) the
80-200/2.8 supposedly is the best choice. Excellent quality, recommended
everywhere.

-Michael