There are jurisdictions that don't recognize PD grants. I can't think of a good reason to use CC0 over MIT or BSD.

> GPL (any version)

This might be doctrinaire but I won't use the (L)GPLv3 because of the AGPL linking clause:

> Notwithstanding any other provision of this License, you have permission to link or combine any covered work with a work licensed under version 3 of the GNU Affero General Public License into a single combined work, and to convey the resulting work. The terms of this License will continue to apply to the part which is the covered work, but the special requirements of the GNU Affero General Public License, section 13, concerning interaction through a network will apply to the combination as such.