Well, on first glance the CC0 sounds good to me:

"CC0 helps solve this problem by giving creators a way to waive all their copyright and related rights in their works to the fullest extent allowed by law"

But the common criticism of CC0 is:

"No trademark or patent rights held by Affirmer are waived, abandoned, surrendered, licensed or otherwise affected by this document."

Which sounds very contradictory to me. I am not "waiving all my copyright and related rights to my works to the fullest extent allowed by law" if I would reserve my right to patent it. I mean, in the EU where I reside software patents are not possible in theory anyway, but I would be allowed to file a patent in the US with the CC0.