[thristian]

IANAL, but:

I don't know of any countries that do not recognise public domain as a concept, but there are many countries (including the USA) whose copyright laws have no provision for an author 'giving up' their copyright. Just saying "I release this into the public domain" does not necessarily do that, any more than walking away from a house you own means you no longer own it. That means that if somebody says "I release this into the public domain", there's no reason why they couldn't change their mind and sue you for infringing their copyright later.

For more information, see this FAQ on public domain: http://linuxmafia.com/faq/Licensing_and_Law/public-domain.ht...

Also note that Creative Commons has a special "Creative Commons Zero" license designed to provide the same results as "I release this into the public domain" in all jurisdictions, and it takes at least a page of legalese to do so: http://creativecommons.org/choose/zero/

TL;DR: saying "I release this into the public domain" probably doesn't do anything; just slap a BSD, MIT or ISC license on the work instead.