apt-get install --reinstall nginx-common не сработало:

Reading package lists... Done
Building dependency tree
Reading state information... Done
You might want to run 'apt-get -f install' to correct these:
The following packages have unmet dependencies:
nginx : Depends: nginx-full but it is not going to be installed or
nginx-light but it is not going to be installed
E: Unmet dependencies. Try 'apt-get -f install' with no packages (or specify a solution).

запустил apt-get -f install, оно мне установило:
Setting up nginx-common (1.2.7-0ubuntu0ppa1~precise) ...
Setting up nginx-full (1.2.7-0ubuntu0ppa1~precise) ...
Setting up nginx (1.2.7-0ubuntu0ppa1~precise) ...

Интересно, что у меня раньше было light или full... =)