Yes there is no amd64 build for unstable (only i386). I suppose there is
a bug in the tool chain to compile unstable version for amd64. So i
suppose this is a temporarily problem.
But in the meantime, you can compile yourself qgis packages with something
like these lines:
# add the deb-src line
Sorry i was not so precise.
I am using the nightly master builds and the latest version of package
qgis is 1.9.90+git20120507+eaff178~unstable1 from 07 May 2012
and of
qgis-common is 1.9.90+git20120520+c64b715~unstable1 from 20 May 2012
So it is not possible to update or use QGIS until there is a
