I'd like to draw the dev list members' attention to a thread from support
about staging:
http://lists.drupal.org/pipermail/support/2008-August/009492.html

The reason I am sending this here, is that I believe there is no structured
and well defined solution to the problem. There are many trials to handle
this (e.g. even/odd nid numbering scheme, dbscripts), but most of them are
cumbersome and/or limited in many ways.

I believe this is a very common problem, and that the only real solution
should come from core. I think the most difficult part here is to separate
content from configuration. The first step would be how to define what is
content and what is config (for example - site name - is it a content
property or a config property?). The next step then would be to find a way to
transfer config from a staging/dev site onto production, without overwriting
any content that might have been added there during development.

--
Yuval Hager
[T] +972-77-341-4155
[@] yuval@avramzon.net