Not 100% sure, but there is no real 'data export' functionality in ezPublish. There really does need to be the ability to export content objects as xml. I do have some vague recollection of a script in the update directory (not in the office now so can't check) but if there is I'm quite sure its for *importing* data.
Its certainly unfortunate but I think they are working on it.
Import/export of content is not possible in 3.3, but is implemented in 3.4. 3.4 has currently only got an web interface for doing import/export, so number of objects is limited.
We're thinking of adding command line support for the import/export of content objects, which will enable you to handle the whole site.
