untrusted?

[Mark Grieveson <dg135@torfree.net>]

Hi.  After a recent upgrade, almost every package, when using aptitude, 
is now listed as "untrusted", whereas before the upgrade it wasn't.  I 
checked my keys:

debian:/home/mark# gpg --list-keys
/root/.gnupg/pubring.gpg
------------------------
pub   1024D/1F41B907 1999-10-03
uid                  Christian Marillat <marillat@debian.org>
uid                  Christian Marillat <marillat@free.fr>
sub   1536g/C28DCC42 1999-10-03
sub   1024D/5D3877A7 2002-08-26

pub   1024D/FBABB737 2005-11-06
uid                  Kirya.net Debian packages verification key 
<debian@kirya.net>
sub   2048g/BD6AB7B6 2005-11-06


I use Etch.  I'm quite puzzled by this.

Mark