According to that Belgian website written in French,
http://www.lalibre.be/article.phtml?id=10&subid=91&art_id=298363
it seems that only historians will have access to these archives.
Last 16 May 2006, eleven countries that are interested in research
had to sign an agreement according to which they will receive a
computerized copy of these archives, so that they can settle the
protection of the data according to their own national laws. The last
signature occurred last 26 July 2006.

In reality, there are no traces left concerning the extermination
itself, which mean no trace of all the people who were sent directly
to the gas chambers immediately after their arrival, without even
entering the camps (without forgetting the numerous persons who died
in the trains during the trip) but these archives concern only the
persons who were sent to work.

Eve Line Blum-Cherchevsky
Besancon (France)
and also
Cercle de Genealogie Juive (International JGS in Paris)
http://www.genealoj.org