FYI: according to Nikon USA web site, this is a Lightweight, durable magnesium body. This may be wrong because they list the D1X interface as USB as well.
As far as when you can get one, the site states, "The new Nikon D100 Digital SLR is scheduled for early Summer delivery. Information about price and authorized dealers will be updated near the time that deliveries will begin. Please check back."
I see that canoga camera is taking preorders for $2200.