Digg has stopped new registrations. If you click the Join Digg link on Digg.com – your are informed that new Digg registrations are closed and the New Digg 4.0 is coming…
Instead you can leave your email address and they will notify you when you can login to the new Digg. It seems they are migrating data to the new Digg and if the new users keep coming in, it would be difficult to migrate.
You can also request an invite to the new Digg alpha and they will soon send you an invite. We recently joined our brand on Digg and you can follow our Digg profile and New Digg profile (if you have access) as we plan to get active on the new Digg in a big way. We have also installed Digg widgets and buttons for quick sharing and you can check them out.