Do you know the pros and cons for both active record and data mapper?

Be PHP-specific, in which the language matters.

Personal encounters are welcome! Ideally with both.

Active record:
advantages:
-simplicity
disadvantages:
-responsibility of storage ought to be a seperate responsability
-static techniques tend to be more hard to test
-persistence frequently globally utilized
-active record frequently mistaken to become the domain object itself (example: cakephp)

see also: http://misko.hevery.com/2009/05/05/the-problem-with-active-record/

Data mapper:
advantages:
-obvious responsability: storing/locating domain objects, no mixing of concerns here
-consequently less complicated to inject persistence collaborators
disadvantages:
-could be overkill on small projects that won't grow

disclaimer: I am strongly biased in support of the information mapper